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Apple Serviceberry
Someone recommended that we grow an apple serviceberry in our yard for the birds. Could you tell me what it is?
Apple erviceberry (Amelanchier x grandiflora) is a wonderful plant that birds love. It grows well in our area in good, well drained but moist soil. This tree or shrub, depending on variety, works very well in the landscape. With its nice silver-gray bark and delicate appearance, it stands out in the garden.  White flowers bloom very early before the leaves appear and the fruits that develop in early summer are redish to purple…but don’t last long thanks to the wildlife. A variety called ‘Autumn Brilliance’ has wonderful fall color while Allegheny serviceberry (A. laevis), a rather large shrub, has bronze foliage in the spring. This one has the purple berries that are most sought after by birds.

Azaleas
Will a potted azalea from Christmas survive if I plant it outside?
It will survive as long as you leave it in the pot and bring it inside before frost. Potted azaleas belong to a family of hybrids that are from the south they are not hardy at all in northern climates. The best thing to do is place it outside in partial shade. The plant should stay in the pot it came in, but if the pot is plastic it may be better to repot the plant into a porous (clay) one. Bury the pot up to the rim in the ground to help hold the moisture. It should stay outside for at least 6 to 8 weeks and needs a period of cool weather in order to flower. In late fall you may have to bring it in at night and set it out again during the day, depending on the weather. Finally, bring it inside, place it in a sunny location, fertilize, and water. If all goes well, you should have flowers by Christmas or New Years.

When is the best time to dig up and replant my azalea?
It is too late if the plant is getting ready to bloom. It would have been better before it leafs our or, if you can, wait until fall. If you have to do it just before bloom, do it on a cool and rainy day so there will be less transplant shock.
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Bayberry
What is the bush that looks like bay leaves and has gray, waxy berries? We have them growing wild all over a nearby old field. They smell nice too. Not being from this area we are curious.
You are seeing bayberry (Myrica pensylvanica). These shrubs grow wild in poor soil and in coastal areas. They fix their own nitrogen from air so they can grow just about anywhere, n fact, they really prefer dry, infertile, sandy soil. Nothing seems to bother them either, not insects, not wind, and not salt spray. The berries were used in Colonial times - and still are - for candle making.

This is a great shrub to have as an ornamental. It is deciduous but the ones in my back field hold leaves until late winter. The berries remain all winter unless the local wildlife takes a liking to them.
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Beach Roses
What are those thorny shrubs that grown along the sand dunes in Charlestown? They smell like roses but the flowers don't look like roses.
They are roses - beach roses (Rosa rugosa), also known as sea tomato and ramanas rose, and I'm sure more names as well. This thorny shrub is essential to sandy areas that are exposed to wind because it establishes hardy colonies rapidly by runners and thereby prevents erosion. Rugosas are a tough shrub, withstanding salt spray, wind, and freezing, and they are resistant to insects and disease.

Rosa rugosa blossoms come in single and double petal varieties, blooming in colors from white to shades of rose through purple, plus a creamy yellow. All colors are fragrant and the petals dry rapidly, keeping their fragrance. The dark green leaves are attractive too, appearing crinkled because of the heavy veining. Blooming continues throughout the summer and into fall and the bright red fruit (rose hips) makes a wonderful jelly.
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Bearberry
Bearberry as I know it has shiny leaves and grows in sand. My neighbor has a plant with duller leaves that looks similar but gets much taller. Which is the real bearberry?
Both are called bearberry. The one you are familiar with is probably kinnikinick (Arctostaphylos uva-ursi). It has dark green leaves about an inch long (wider at the end) that are very glossy; it grows to about a foot high and thrives in sand. Kinninkinick is found on the dunes of Cape Cod, the shore along Lake Michigan, and on the Pacific coast. It will generally grow throughout the cool, northern climates of the world. It has flowers similar to blueberry blossoms in the spring and red berries in the fall.

Your neighbor most likely has bearberry cotoneaster (Cotoneaster dammeri). Its leaves are actually a bit longer, sort of pointed at both ends, and the undersides are fuzzy. It can grow to three feet high and much larger around. The flowers of the cotoneaster are also bell shaped and larger, but do not grow in clusters like those of kinnikinick. Both plants are very adaptable to a variety of soil conditions but Cotoneaster prefers a rocky blend.

Finding different species of plants bearing the same name can be confusing, so it's important that we learn the proper botanical names, as well.
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Beautyberry
How do I prune my beautyberry bush?
Beautyberry (Callicarpa) is pruned late in its dormant period because this shrub produces berries on the current season’s growth. Each spring, they pop back from the roots, so in early to mid March cut them back to either green wood or to ground level. Always remove dead, damaged or rubbing branches. In our Zone 6, beautyberry freezes back to the ground, or almost to the ground, in winter depending on how cold it is.
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Bittersweet
I just made a door wreath with vines that have orange berries and my neighbors are upset about it. What is the problem with these vines, are they poisonous?
The problem is that you are using an invasive plant called Oriental, or Asiatic, bittersweet (Celastrus orbiculatus). It was brought to this country as an ornamental back in the 1800s but it has since become naturalized over much of the northeast. It can be found along the roadsides and in other uncultivated areas where it forms thickets. Bittersweet chokes or strangles shrubs and trees by girdling them as it twists and turns upward. The leaves turn a lovely yellow in the fall and then drop off, leaving behind those yellow fruits with red-orange seeds.

This vine reproduces rapidly by seed which is most likely why your neighbors are upset. Nobody wants to have it growing in their gardens. Learn to recognize this weed by the rounded leaves and pull it out. The roots are also red-orange. Chances are you are going to be contending with this in your own yard. There are some reports that say the seeds are poisonous and although I cannot find a definite statement I imagine they could make one very sick.
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Bleeding Heart
My bleeding heart plant has disappeared. I went to clean up the garden and it wasn’t there. What happened to it?
It’s there, but it’s under the soil, unless drainage was poor and with too much rain or watering days standing water rotted the crown. Bleeding heart (Dicentra) doesn’t like heat, so in the hot days of summer these plants die back, that is why it’s important to mark the spot. As long as the planting location is elevated so it drains well and water won’t accumulate there shouldn’t be a problem. Check by digging gently into the soil for roots. If you find them, your plant will return next spring.
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Boltonia
Last fall, while visiting some friends in Connecticut, we spotted a very tall aster. It must have been 6 feet high and the flowers were pinkish to white. Is this a wild flower or something that we can buy at a nursery?
I believe you are describing Boltonia asteroids. This is a tall aster-like perennial that thrives in any good soil and spreads rapidly, especially in moist soil. It can reach 7 feet in height and definitely needs staking. The larger garden nurseries should carry this plant, but if not you can order the seeds from any reputable seed company. There are also low-growing varieties available, such as Boltonia ‘Nana’.
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Boxwood Psyllid
Last fall our boxwood had black mold growing all over it and yesterday we noticed that the leaves at the end of the branches are curled up and it looks like the bud that would send out new growth is dried up. What is causing this and what can we do?
When the leaves open, look for a very tiny gray-green insect. You may also soon see small flies bouncing around the plant while the leaves develop a shiny coating. You are seeing boxwood psyllids (Psylla buxi) at work. The immature form of this insect feed by sucking sap from leafs, which makes them turn yellow and curl or cup. As it feeds the psyllid secretes a whitish waxy coating that protects it from preditors and water. And, because the psyllid cannot digest all of the juices, the excess is excreted as honeydew which forms a sticky coating on leaves. The black mold you saw was a growing on the honeydew. This insect matures in early summer and females lay eggs in the bases of buds in the fall. The process starts over again in spring.  A systemic insecticide used as directed will control these pests for you.
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Broom
How do I prune my broom?
Broom includes three different genera: Cytisus, Genista and Spartium. Some are small spreaders, some are evergreen, while still others are deciduous. Those that flower have green stems. If your broom is old and twiggy, don't even try. Old wood very seldom regenerates. Otherwise, cut the stems not more than one third after flowering but don't cut back into the old wood. This should rejuvenate the shrub for the next blooming season.

Bugbane
What is bugbane?
Bugbane (Cimicifuga), sometimes called bottlebrush because the flowers resemble just that, is a nice woodland plant for shady areas as long as the soil is rich and moist. The plant looks wonderful in a shade garden mixed in with ferns and other perennials. It sort of dances above the foliage of other plants and can get to 6 feet tall depending on the species.

Black snakeroot (C. racemosa), a native of eastern U.S., can get very tall. Other popular forms are Kamchatk bugbane (C. simplex), C. japonica, C. dahurica, C. foetida, C. americana, and C. ramose, another tall one. All are rather difficult to start from seed but these plants are available from specialty nurseries.
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Butterfly Bush
What happened to all the butterfly bushes? Some didn't come back this spring and others are so very late blooming.
Blame it on the weather. Butterfly bushes (Buddleia) are tender shrubs that frequently are killed back to the ground in cold northern climates, especially if it is very cold for a long period. However, they flower on new growth so it doesn't hurt the plant whether they die back or you cut them back to the ground each spring. I'm surprised that some were late in blooming as they grow very rapidly. Perhaps those late bloomers were daughters of the older ones and are just getting established.

Buddleias prefer rich, well-drained soil and full sun. The faster they grow, the bigger the flower clusters will be. But they can become somewhat of a nuisance, with a habit of growing anywhere, like between bricks in patios and pools, even in a crack in the asphalt.

What is summer lilac?
Summer lilac is just another name for the butterfly bush (Buddleja davidii), a deciduous shrub that is planted in gardens to attract butterflies. It was given the name summer lilac because the flowers resemble lilac blossoms, being multiple single flowers arranged in an upright spike. This shrub can easily grow to 10 feet with branches that are very long and arching. Depending on the cultivar, the blossoms are mostly purple to red, though white is available. Butterfly bushes like full sun for optimum bloom and will reseed readily. They are sometimes considered invasive. The growth freezes back during the winter and new shoots may be sent up from the roots. Prune these plants back each spring to about a foot per stalk to force new growth.

How do I prune a butterfly bush?
Most butterfly bushes in our area (Zone 6) are Buddleia davidii which die back to the ground each winter, so in spring we cut them back either all the way or leave a few inches, depending on how many of the lower buds make it through. However, this species flowers on new growth so you won’t lose much by hard pruning. Buddleia alternifolia, on the other hand, bears spring flowers on last years growth so it should be pruned after flowering. Cut back the oldest wood to the ground to create new stems and, with both of these types, always cut out broken or rubbing branches at anytime.
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Catnip
Nepata is supposed to be for my cats but they didn't like it at all because of the very sharp odor. What is true catnip that is sold at the pet stores?
The real catnip plant is Nepata cataria. You probably planted catmint, another of the Nepeta species and a lovely perennial for flower borders. Catnip is also a perennial but it looks and smells quite different. It grows to about three feet tall, has pale green leaves that are downy, and small lavender flowers. Catnip will grow just about anywhere in good soil, but it really takes off in rich sandy loam which creates the best fragrance. The plant is not fussy about sun or shade either. If you plant seeds in the fall, you will have a good crop the following year, and if some are left to seed they will return.

Start harvesting as soon as the plant reaches about eight inches high by cutting it back to four inches. This creates new bushy growth and each time you clip some off it will continue to increase. Do this until mid August then let it set seed. Dry your cuttings in the shade to maintain a good color and strong aroma. I grow it myself and bring in a handful of short stems and leaves weekly that are placed in hanging baskets to dry.
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Clematis
Is clematis hard to grow?
Like any perennial, as long as you meet their needs they do fine and are very hardy. Most varieties need full sun but some shade during the hottest summer days is helpful. Those with dark color flowers really need that shade because the blossoms will fade with excess sunlight.
Plant clematis on the east side of your home. Here's the trick to keeping them happy: make sure the roots stay cool and moist by heavy mulching, and don't plant where snow will be piled up on them during winter months. The soil they are planted in must be deep, full of compost, and the pH needs to be a neutral 7. Clematis may like moist roots but they do not like standing water, so make sure there is good drainage.

Another thing to consider before planting is whether they going to climb up or sprawl? Dig a hole big enough to accommodate the root system and prune the stems back to about a foot in height. This will force branching as the plant grows. Also, plant the crown below the soil level by one to two inches. Growth will be slow during the first season so don't expect flowers. But once the roots are established, there may be no stopping them.

How do you prune clematis?
Pruning is determined by the type of clematis you have. There are three groups of clematis; early flowering (early spring), late flowering (late summer), and large- flowered hybrids. The early flowering types produce blooms from buds produced the previous summer and pruning is done after blooming has finished, but no later than mid-July. Late-flowering clematis bloom on the top portion of current year's growth and should be pruned back in late winter to two or three feet high.

Hybrids often bloom twice in one season, in late spring on growth from the prior year and again in late summer on the current year's growth. So prune all dead wood in late winter and cut back the rest of the branches only to the top pair of large green buds, which could be anywhere from two inches to two feet from the tips of the stems. The hybrid clematis often has bare stems at the bottom. You can cut the vine back to about eighteen inches right after the first bloom to force a second flowering if you choose. Pruning is a must if you want the maximum amount of flowers and to keep the vines healthy. Don't panic if you make a mistake, the plant will recover.
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Crown Vetch
I have a very steep, almost vertical, slope in my yard and was advised to plant Cornonilla on it. What is this plant and where can I get some?
Coronilla is crown vetch, a very reliable plant for erosion control on steep slopes. It blooms from early summer to frost with clusters of pink to white flowers, somewhat resembling clover. Crown vetch spreads vigorously and grows to about 18 inches in height. You should get plugs sprouts so the seeds wouldn’t be washed off your slope before they germinate.
I don’t recall seeing any seedlings locally but I’m sure one of our nurseries would either have it or can get some for you. Check with farm suppliers first and then seed suppliers before checking with nurseries.
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Daylilies
I've ordered a bunch of day lilies to plant in the spring. Do they have any special needs?
No, just the normal type of care. Daylilies (Hemerocallis species) are tolerant of almost anything that comes along. Even though each flower only lasts for a day, there are so many buds on a healthy, established plant that you could continue to see blooms for a month. They do like a slightly acidic soil (pH around 6), good drainage, and a sunny spot, though they will tolerate some shade. Plant them about 2 feet apart, set so that the crown is not more than an inch below the surface. Water them thoroughly after planting and give them a deep watering once a week. They are drought tolerant but good, consistent watering while the buds are forming will produce better flowers. Fertilize in early spring as new growth emerges with a 5-10-10 blend as they prefer more phosphorous and potash than nitrogen. Mulch to control weeds and to hold moisture in the soil.

After flowering, cut off the dead blossoms and any seedpods to encourage more blooming. At the end of the season, cut off all the scapes, or flower stalks, but let the leaves die back on their own. When the clumps become overgrown, divide them and replant; this should be done as soon as flowering ends.
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Dame's Rocket
I'm looking for information about dame's rocket.
Dame's rocket (Herperis matronalis), also called dame's violet and sweet rocket, grows very well in our area as a short lived perennial. It was a favorite of cottage gardens in Europe and was introduced to this country by early settlers where it escaped and became naturalized.
Just sprinkle the seeds on the surface where you want them or start them in pots during the summer for next year's bloom. Dame's rocket grows to become a clump of spikes, about three to four feet tall with very narrow leaves. Flowers start blooming at the bottom of the top third of each spike and continue up to the top. If you deadhead them, more side shoots will appear. This plant self seeds but usually doesn't become a major problem. The flowers are soft lavender, with some being darker or lighter, and all are scented. This plant likes damp soil, full sun or partial shade, and loves growing along the edges of the woods.
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Deciduous Hedges
We have a hedge but don’t know the type of plant it is. It loses all the foliage in winter and when pruned in summer it turns brown and looks awful. Is there something we should be concerned about?
Yes, the method of pruning. Deciduous hedges, especially those with larger leaves, suffer leaf damage when trimmed. The shears, electric or otherwise, often cut through a leaf leaving the other part to turn brown and die back. This makes an unsightly hedge until the damaged parts have been covered by new growth. To avoid this, try using pruning shears and cutting individual branches. I know, this is the slow method, but it does avoid the half dead appearance which, by the way can lead to disease problems.
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Disanthus
What is a disanthus shrub?
Disanthus is a shrub related to witch hazel that is native to the woodlands of East Asia. Disanthus cercidifolius has wonderful fall coloring but is not easy to grow. It needs moist, very rich, and lime-free soil and light shade. This shrub doesn’t tolerate wind very well either. The plant grows to approximately 8 feet high and it has smooth, heart-shaped leaves that are sort of bluish green. The fall colors run from a lovely shade of orange to purple just before the very pale small lavender flowers appear. Disanthus is supposed to be hardy to Zone 6.
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Drought-tolerant Shrubs
Can you give me a list of shrubs for an area in our yard that is very dry?
Try Rosa rugosa, bayberry (Myrica pensylvanica), some viburnums, flowering quince (Chaenomeles speciosa), smokebush (Cotinus coggygria), lilac, witch hazel (Hamamelis virginiana), beach plum (Orybys narutuna), and privet (Ligustrum). Of course, no plant can survive without some water but these and a few others do well with the minimal amounts once they are established. For more choices I suggest you check the Sustainable Plant List on our website.
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English Ivy
Before we had our chimney repaired, it was covered with ivy. This was removed and we replaced it with honeysuckle but it doesn’t climb and cover the surface like ivy.  Are the new bricks the problem?
No, it isn’t the bricks. Ivy, at least English ivy (Hedera), climbs by using aerial rootlets that grab and cling to the surface material. Honeysuckle (Lonicera) can’t do this, instead, it climbs by wrapping it’s stem around something, like the branch of another plant or a trellis. If you would like the honeysuckle to cover the chimney, place chicken wire around the chimney for the plant stems to entwine.
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False Indigo
Someone just gave us an Amorpha and said it would have blue flowers. What kind of plant is it?
You probably received Amorpha fruticosa, which is false Indigo, a deciduous shrub with feather-like foliage or leaflets. This plant will produce spikes of blue to purple flowers in early summer. It can get to a height of about 12 feet, so place it where it will have enough room. False Indigo will die back in the winter in our Zone 6 but quickly pops back up come spring. It wants full sun and regular watering - an inch a week will keep it happy. This Amorpha is a leggy bush but responds well to pruning in the early spring to thicken it up. Another Amorpha is A. canescens, or lead plant, but I don't think this would be the one unless they had traveled out west or to Canada.
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Fertilizing Shrubs and Trees
Is it too late to fertilize evergreens particularly andromedas, rhodys, azaleas, hollies, as well as flowering trees, that have already blossomed? If not, what fertilizer combo is best?
I would not fertilize flowering plants while they are flowering. Do it a couple of weeks before or after. Use an all purpose 5-10-5 or 10-10-10.

Geraniums
I want to start some new geraniums from the ones in the garden, what is the best way to do this?
Take cuttings that are 3 to 4 inches long from the ends of the plants and remove the bottom leaves. Dip the end of each cutting in a rooting hormone and place it in a container with either plain, sharp sand, or a mix of peat moss with perlite or sand. Stick them into the potting mix to a depth of about 1 inch and water them well. Put the container of cuttings in an east or north window and keep the soil temperature at about 72 degrees. In 3 to 4 weeks, they should be rooted. Be careful with the water as too much will cause the cutting to rot away but you don't want them to completely dry out. Test by giving the cuttings a small tug; if there is resistance, they have probably developed roots and can be planted into larger pots. Then they should be moved to a brightly lit but cooler area.
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Goldenrod
While browsing through a new plant catalog I noticed that goldenrod is offered as a perennial for the flower beds.  Isn’t that aggravating to someone who suffers from hay fever?
Not at all. Goldenrod (Solidago) isn’t pollinated by the wind but by bees and other beneficial insects, which means the pollen is not in the air to breath. Goldenrod has always taken the blame for being an irritant but the real culprit is ragweed (Ambrosia artemisifolia). 
The goldenrod plants offered in catalogs are hybrids that have wonderful textures and variations of a golden color. Like other plants taken from their wild relatives, goldenrod can spread but pulling them out every fall will keep them under control. Goldenrod is not fussy about location or soil, making it a wonderful filler for difficult places.
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Grape Holly
What is grape holly?
Grape holly (Mahonia aquifolium), often called Oregon grapeholly, is a very showy shrub with yellow flowers in mid-spring followed by blue fruits. Mahonia makes an ideal specimen for planting alone or with other shrubs along a foundation. The leaves of this shrub do resemble holly leaves and they are evergreen, but during the cold of winter they turn bronze. Keep Mahonia out of the sun and wind and in a soil that is acidic, rich, and moist; if exposed to wind and sun it will scorch. The plant often looks straggly unless it is pruned, but it can be kept neat and held to an established height. It is an evergreen ground cover in some areas even though it can grow to a height of six feet. Mahonia aquifolim is hardy to Zone 5 but other varieties are only marginal in our Zone 6 or need a warmer Zone 8.
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Ground Ivy
There's a vine growing all over our yard that resembles a geranium. It smells nice and has purplish flowers. My neighbor calls it cats foot and says it's an obnoxious weed. Is it a weed and what is its real name?
Cats foot, field balm gill-over-the-ground, and creeping Charlie are all the same plant - it's ground ivy (Nepeta hederacea), a perennial weed and a member of the mint family. If it didn't spread so rapidly it wouldn't be a bad ground cover. The stems trail along the ground and root at each node. The leaves do make one think of a geranium but the leaves of ground ivy have teeth. The leaves grow opposite each other along the stem and in the spring flowers appear with the leaves on the upper portions of shorter stems. It likes damp, shady places but will grow just as well in the sun, plus, it remains green all winter long. The easiest way to keep it under control is to pull it up. You will be surprised to see how much comes out with one tug. Ground ivy can really be a nuisance when it creeps into the strawberry patch!
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Guara
There’s an ad in today’s paper for perennials and I’m wondering if all of the plants are hardy here in RI, especially the Guara?
The general rule is that you have to find out about a plant’s requirements. As for the Guara, it is a native of Texas and Louisiana but it is generally rated to be grown in zones 5-9. It can thrive in heat and humidity and, due to a deep taproot, it can withstand drought. It requires rich, well drained soil and can naturalize in good growing conditions and deadheading extends the blooming time. Colors range from white to rose. Guara lindheimeri can grow to three feet or more. I think I would try planting it in a protected area, giving it a good mulch protection for the winter, just to see how it does. It may not appreciate our wet, cool, extended spring weather.
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Hamamelis
What is Hamamelis?
Witch hazel, a fragrant flowering shrub or small tree of East Asia and North America. It flowers on bare wood in the cold of late winter. In the fall, the leaves turn yellow with orange and red tones and a small two-seeded fruit appears. Witch hazels prefer an open, sunny spot with damp, but not soggy, acidic soil. They can be raised from seed but takes a full year to germinate; most forms are propagated by grafting or cuttings. All forms of Hamamelis are hardy in our Zone 6 except H. virginiana.

Hamamelis x intermedia includes a group of cultivars that have flowers ranging from yellow to a dark coppery tones: 'Arnold Promise' has golden yellow flowers, 'Diane' blossoms in spidery reds, 'Jelena' is bright orange, and 'Ruby Glow' blooms in a dark copper color. This species grows to a height of around 15 feet while H. vernalis, called Ozark witch hazel, only grow to height of six feet. H. vernalis flowers in spring and spreads by means of suckering. The flower is yellowish with a dark red spot in the center. H. virginiana, common witch hazel, can be trained into a tall tree, growing to 20 feet or more, and its blooms appear in autumn as the wonderful butter yellow foliage falls.
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Hardhack Bush
What is a hardhack bush?
I love these odd names! Hardhack is steeplebush (Spiraea tomentosa); many people mistakenly call this plant meadowsweet. The small oval leaves grow up the stalk and they are dark on top and brownish beneath; the bottom of the leaves resembles rust-colored flannel. The bush establishes in old fields where it grows in clumps to a height of about three feet. Each stalk is topped with a cluster of rosy purplish flowers arranged in spires. If you examine each flower on a cluster you will see five spreading petals with a profusion of stamens in the center which give the plant a feathery appearance from a distance. After the petals fall off, the flower spike can be dried and used in flower arrangements.
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Hazelnut
I need some information on growing hazelnuts - I'm looking for the shrub type.
Hazelnuts, or filberts, (Corylus avellana) tend to grow into large shrubs because they sucker and form thickets but they are often trained into small trees. The hardiest types for our climate - the European and the cross between the European and the American species - have the ability to withstand cold temperatures. You will need two plants to enable pollination. Filberts fit well into gardens when treated as a shrub and can be planted to form a nice hedge.

Filberts prefer fertile, well-drained soil that is slightly acidic, however, they do well in just about any type of soil as long as there is good drainage. Full sun is a must for the best nut production, but that won't come along for at least four years. You won't have to use a fertilizer as long as the leaves stay green and production is good. Otherwise, a small amount of nitrogen at the start of each growing season will suffice.

Some of the best varieties are Barcelona, Butler, and Royal. There is also a hybrid called Fingerlakes Filbert Super Hardy.
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Hebe
A local grocery store is selling a plant called Hebe in its plant department. What is it?
Hebe , which is know as shrubby veronica in some areas, is a perennial evergreen shrub that is native to New Zealand and South America . Hebe is not hardy in our area, though some varieties are listed for Zone 6. The Hebe being sold at super-markets is probably one of the smaller types which are treated as houseplants. One of them is H. alvicans ‘Red Edge’, a dwarf having gray to bluish leaves with a narrow red edge.
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Hellebores
What is a Christmas rose?
It is the hellebore Helleborus niger, a very different perennial plant that blooms during the cold weather. The Christmas rose is a member of the buttercup family and it loves shade and humus soil; it is very happy beneath trees, especially along the edge of the woods. Christmas rose will bloom from December to spring, depending on the type of winter we have. It has dark green, leaves with jagged edges that are divided into leaflets. The greenish flowers turn purple as they age. Some species are evergreen and last a long time. Once they are planted, don’t move them.
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Holly
I was told my hollies have iron deficiency. Can you give me information about this?
Iron deficiency is often a problem with acid loving plants like hollies, azaleas, blueberries, and others. For some reason the pH of the soil has been raised, perhaps from liming or leaching lime from building foundations. If the pH is too high for these plants, they cannot absorb the iron, which is usually sufficient enough in the soil. The leaves, especially the younger ones, turn yellow but the veins stay green. It's very noticeable.

To quickly rejuvenate the plants, spray them with chelated iron; you can purchase this from any large garden center, and just follow directions for applying. To lower the soil pH, add peat moss or sulfur. Be sure to get a soil test done to see how much is needed.

My friend in New Jersey has a beautiful holly that has dark shiny leaves with only one thorn at the tip. The berry clusters are just gorgeous. She calls it holly birdie but I can’t find it anywhere. Can you help me?
The clue is the single sharp spine on the end of the leaf and its dark green color. Birdie probably refers to the ‘Burfordii’ cultivar of Ilex cornuta, a shrub with a handsome growth habit. This holly can develop into a small tree of 20 feet or more. It’s listed as hardiness Zone 7, but it might survive here in Rhode Island with good protection. Burfords berry freely and without pollination, and the fruit lasts for months, providing a food source for birds into late spring. Dwarf Burford hollies ( I. cornuta burfordii 'nana') do not produce berries as heavily but they have other qualities of the full sized varieties. A dwarf may be used where a shorter shrub (5-8 feet) is preferred.
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Honeysuckle
Before we had our chimney repaired, it was covered with ivy. This was removed and we replaced it with honeysuckle but it doesn’t climb and cover the surface like ivy. Are the new bricks the problem?
No, it isn’t the bricks. Ivy, at least English ivy (Hedera), climbs by using aerial rootlets that grab and cling to the surface material. Honeysuckle (Lonicera) can’t do this, instead, it climbs by wrapping its stem around something, like the branch of another plant or a trellis. If you would like the honeysuckle to cover the chimney, place chicken wire around the chimney for the plant stems to entwine.
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Hydrangea
I have hydrangeas and don't know when and how to prune them.
It depends on the type of hydrangea you have. Hydrangea arborescens is usually cut back to the soil in very late winter or early spring since it flowers on new shoots; it usually dies back during the winter. If it's an older plant that doesn't succumb entirely, just prune some branches to the ground and cut the rest at about 18 inches from the ground.

H. paniculata, which has white flowers in the fall that turn pink and hang on, are pruned by removing the dried flowers or some of the shoots if you want to keep it under control. It also flowers on new wood. This variety can be pruned into a tree form.

H. macrophylla, which blooms pink or blue depending on soil acidity, is pruned in late summer as soon as the flowers have faded. Remove weak shoots - both old and new - at the base. This plant blooms only from the tips or end buds of lateral shoots on old stems, so spring pruning will result in a poor showing of bloom for the year. However, the new 'Endless Summer' blooms on new and old wood, so it can be pruned any time.

H. quercifolia, the oakleaf hydrangea, is pruned in early spring only to remove dead wood. Climbing Hydrangea (H. anomala petiolaris) requires no pruning, just trim it to control its size.
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Someone said that if you put rusty nails in the hole before planting a blue hydrangea it would make it more blue. Is this true?
No. The rusty nails will add more iron, which is fine if the leaves of the hydrangea are turning yellow. An iron chelate will do just as well to solve the problem. However, the blue color of the flowers is due to acidic soil reacting to aluminum compounds that are always present. If you want pink blossoms, you need alkaline soil that will block the aluminum compounds from being taken in by the plant.

Our hydrangea is turning brown in the center and some leaves are falling off. What should it be sprayed with?
Nothing. Don’t spray it. I don’t know where your plant is located, but what you are experiencing is sunburn. Hydrangeas don’t like hot sun; leaves turn yellow then brown, and some will fall off. Lack of water makes this problem worse. Try shading the shrub and if it’s small enough to move, do so in the fall. Water it well on the days that you can.
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Inkberry Holly
What is the name of the holly with little black berries and no spikes on the leaves?
This shrub is inkberry holly (Ilex glabra). It is an evergreen with small, smooth leaves and lots of tiny black berries that ripen in the fall and stay on the shrub until spring. It is a slow grower that likes damp, but not soggy, soil, and it isn't fussy about light - full sun or partial shade will do.

Inkberry makes an excellent hedge or foundation planting, doesn't mind being cut back to maintain height and is mostly pest free. Deer like it in the winter - at least they liked mine! If it is attacked by deer, prune heavily to renew it. Keep it pinched and it will form a nice thick bush. There are some nice varieties of this shrub to choose from: 'Compacta', 'Densa', 'Shamrock,' and 'Nordic' are a few of the most popular.
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Lilacs
How do I prune very old lilacs?
Lilacs bloom on old (last year's) wood, so for those branches that have flowers this year, remove the spent bloom just above the first set of leaves below the flower cluster, then prune out any dead or decaying wood. Old lilacs spread, so the center of the bush eventually dies back while new shoots come up all around the area. These new shoots can often be dug up with some roots attached and then replanted elsewhere.

After cutting away the dead and old wood, prune back the shoots that did not flower and have only one bud on them (look for elongated buds sticking out) as they are just sapping energy from the shrub. Shoots with two buds will produce blossoms the following year. You can remove a third of the oldest stems each year for about three years to ensure that the shrub will produce flowers. After a few years of this, the bush should be full again.
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What is the difference between lilacs and lilac trees?
They are actually both species of Syringa but differ due to variety, height, and training. The common lilac, S. vulgaris, can easily grow to a height of twenty feet with an equal spread. In fact, most varieties average six or seven feet tall, but the one most commonly referred to as a tree is S. reticulate which is also known as S. japonica or S. amurensis japonica. This is the Japanese tree lilac and while it can grow to thirty feet or more it will be a shrub until trained into a tree with a single trunk.

The leaves on our lilacs and viburnums are curling up. Is this from lack of water? We live in Kent County where outside watering is restricted.
Yes, the problem is lack of water and it will only get worse during a long, dry and hot summer when watering restrictions are imposed. The day you can water, make sure you soak the plant root areas, and soak deeply. It’s the water pressure inside the plant’s cells that keeps the leaves from curling. When the roots can’t get enough water, the cell walls collapse. Eventually the stems will also be affected. Also, keep the root area mulched to help retain soil moisture.
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Lily of the Valley
Is Lily of the Valley poisonous? How easy are they to care for?
Only the berries are poisonous. Lily of the Valley (Convallaria majalis) is a very easy plant with a wonderful fragrance. Planted in a shady, moisture-retentive area this plant can easily establish a nice ground cover. Sometimes it grows too well and becomes invasive. Lily of the Valley will even grow under black walnuts where most plants won't and it has also been known to grow beneath snow cover in the coldest zones.

Set the rhizomes a couple of inches below the surface in a slightly acidic, humus soil in early spring. Before long, shoots will come up and open into a pair of shiny leaves. Shortly afterwards, a skinny stem with buds will appear beside the leaves, not between, and open into small white or pink bells, depending on the variety. In fall, when the leaves die, a spike of bright red berries will appear at random throughout the plantings. Once established, they crowd out the weeds but until then a little hand pulling is needed.
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Matrimony Vine
Can I grow matrimony vine in Narragansett?
Probably. Matrimony vine (Lycium barbarum), or Chinese box thorn, is hardy in Zone 6. You do have to keep an eye on it; it may become intrusive as it spreads rapidly by suckers. It really isn’t a vine, although the branches arch to resemble a vine. It is a deciduous shrub, often with spines that grows upward to 10 feet or more. The plant is covered with purple flowers during the summer and red berries in the fall. This shrub is not fussy about soil and will easily anchor into sand. There are other varieties of this shrub but not all are hardy up north. And, some states have placed this species on their invasive list. So I would hesitate before planting any.
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Mertensia
What is Mertensia?
Mertensia is Mertensia verginica, commonly know as Virginia bluebells. This is a perennial that goes dormant during the heat of summer. Mertensia springs from forest floors in early in spring in Zones 3 –9. At first the buds are pink but open to reveal tubular blue flowers that hang over the gray-green foliage like bells. These plants grow to almost two feet tall and spread almost as much. Bluebells need rich, moist, but well drained soil and partial shade. If you are going to grow them, the leaves will turn yellow in June and start to die back. At this point, do not cut away the foliage but allow it to die naturally. For the most part, Mertensia is trouble free.
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Montauk Daisy
My Montauk daisies get tall and fall over. Someone said to trim them twice a year but didn’t say when. Can you tell me how and when it’s done?
Montauk daisies (Nipponanthemum nipponicum) do get leggy, floppy, and out of control. You can cut them back twice during the growing season: the first time is about the middle of May when you see the growth starting to swell; the second time is during the last week of June. In May, cut them back to 4 inches; in June, cut one half of what has grown since the May cut. You are cutting about six weeks apart. Don’t do anymore trimming after the last week of June. Your daisies should be sturdier and less likely to flop onto neighboring plants.
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Peony
My peonies will not bloom. I only get one flower. What will help?
Peonies need full sun and a pH of 6.5 or higher. They are very fussy about the depth to which they are planted: in the prepared hole, the eyes (small, red-colored buds) should be one to 2 inches below the soil's surface. They enjoy a lot of food; compost is a good start in the planting hole. Follow up with a 5-10-5 fertilizer early in the spring and after bloom season. Peonies also hate to be moved, so don’t unless you have to. This is best done in early fall.
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Planting Shrubs
What is the proper way to plant a balled and burlapped shrub?
First, as with all shrubs, choose your location carefully as the size of the full grown shrub must be considered. Also, the soil needs to drain well.

Dig a hole with a depth equal to the size of the root ball and twice as wide. Soil amendments will be necessary only if you have all sand or hard soil. Place your shrub in the hole, and with the bottom of the root ball sitting on solid ground the top should be at ground level, or just above it. Cut and remove the tying material and open up the burlap then push it down; if the shrub is not too large, remove it completely. It is important to be aware that synthetic burlaps will not rot away and must be removed.

Fill the hole with the dug soil a little at a time making sure that there are no air pockets. Continue to do this until the soil level is an inch or so below the ground level. Then prepare a berm around the hole to create a trough that will hold water. Fill this depression with water and let it settle in, firming up the root ball as it does. If the root ball settles a little to low, raise it with a shovel until the muddy fill has gotten beneath it. Be careful not to cover the crown, that is, the base of the shrub where the stems meet the roots, as moist soil around the crown will cause it to rot. Mulch lightly - keeping the mulch away from the stem - and keep the shrub moist (water every day for the first week) but not soaked. Water deeply to encourage good root growth.
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Poppy
I planted two big, red poppies this spring. They bloomed and gave me a nice seedhead for decoration but now the plants are turning black and dying. Help?
Poppies (Papaver) will do that. They bloom early in the season, produce seed, and then go dormant. The foliage is “melting away” because poppies can’t tolerate hot weather. As long as the roots have good drainage, especially in winter months, they will be back next spring. Give them a good mulching after the ground freezes to avoid frost heave which can devastate the plants.
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Pruning Shrubs
Can you please give me a list of shrubs that have to be pruned before they bloom?
Although it seems confusing, the rule is that you can prune any shrub that blooms on new wood before blooming, but those blooming on old wood have to wait until after they bloom.
The following shrubs need to be pruned before they start growing: butterfly bush (Buddleia davidii), Clethra, Rose of Sharon (Hibiscus syriacus),  smooth hydrangea (Hydrangea arborescens), and H. paniculata ‘Grandiflora’.  Be absolutely sure of what hydrangea you have because the bigleaf (H. macrophylla) and oakleaf (H. quercifolia) types are done after flowering. Also, you can prune shrubby spireas – not the bridal wreath variety – Callicarpa, beautybush, Caryopteris (sometimes called bluebeard), and repeat-blooming roses. 
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Pussy Willow
I would like to plant some pussy willows so that I can use the branches for decorating. Is this feasible?
Pussy willow (Salix discolor) will grow well in any soil that has a lot of leaf mold or compost in it. They like full sun, but will tolerate some shade, and they do need lots of water. They're very easy to propagate as they root easily by simply sticking cuttings from new growth into moist soil in the spring.

Often, cut branches brought inside for decoration will root if not set in a sunny location. To maintain pussy willows for decorative cuttings, prune after the flowers have finished as they bloom on the growth of the previous year's wood. You can hard prune pussy willows to get longer stems and larger catkins. If left unpruned, pussy willows grow into a straggly tree form, so every three years, cut them back to 6 inches of stump.
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Pussytoes
We have an area near our sidewalk where the soil is poor and our lawncare person suggested we plant some Antenna dioica but we can’t find it anywhere. Is this a plant or do we have wrong information?
You need to ask for Antennaria dioica or, as it is commonly called, pussytoes. This is a gray-green ground cover that spreads rapidly, forming a mat of leaves as it spreads, and tolerates poor soil and dry conditions. It makes a quick filler where cover is needed but only grows about 6 to 8 inches high. You may have to pull some out to keep it under control. Small clusters of pink flowers appear in late spring on light green stems for the ‘Rosea’ variety; flowers are creamy white flowers for ‘Tomentosa’. The name pussytoes comes from the resemblance to cat’s toes.
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Relocating Perennials
We are moving to Texas this fall and want to take some of our perennial plants with us. How can we accomplish this?
First, check to see if Texas will allow you to bring all your plants along; many states have restrictions because plants can be invasive out of their 'natural' environment. Second, will they grow in the zone you are moving to? Many New England plants will succumb in the heat and high humidity that you may encounter.

For those that you can take, either divide them or pot them up this spring; if your move is in late fall, you can do this then. Long rooted or larger established plants will not take to being disturbed so try to start new ones. Getting your plants settled into pots is the best method of transporting them.

Next, how are you going to do this? Placing plants in a moving van is out of the question. They need light and water, plus, being inside a container is going to heat them up. Air freight can be just as damaging. Moving them with you in a vehicle is the best way. Still, you will have to watch them carefully for reaction to sun coming through the vehicle's windows, air conditioning, and wind coming in through open windows. Also, if you can set the pots into a plastic tray with deep sides, this will help avoid spillage and leaking water. And, don't forget overnight care. In doing your planning, be prepared for any problems that might occur.
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Rhododendron
My rhododendron leaves look like someone used a hole punch on them. What caused this?
Black vine weevil, a tiny, black or dark gray, snouted beetle with wings that have gold flecks on them. It usually spends the winter as a larva in the soil around the roots of plants it likes to feed on. If they can find good shelter, some adults will overwinter. The larva resumes feeding on roots in the spring, pupates in the soil, and emerges as an adult in mid June. After feeding on the leaves for a couple of weeks, the female will lay eggs around the crown of the plant which will hatch about 10 days later and the cycle begins again. The problem is that the adult feeds at night – undetected unless you check with a flashlight. Use Bacillus thuringiensis (B.t.) to get rid of these pests.
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Help! The deer ate parts of our rhododendrons over the winter. Will they come back? When can they be pruned?
If your rhododendrons are old enough and healthy, there is a chance they will survive. First thing is to put some sort of barrier around them now, perhaps a circle of tall fence set back so the deer can’t reach over the top but close enough that they won’t jump inside. Or, you can toss one of those black plastic nets over the shrubs. This will stop them from finishing off your plants. Then in early spring when the snow is gone prune shredded branches back to a bud and give the shrub a boost from compost spread around the root zone. Don’t use too much fertilizer because the plants are stressed and don’t need extra stimulation.
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I have rhododendron bushes growing in my yard. A lot of the leaves on most of these bushes have black spots. What are they, and can I do anything about it?
It's very common in some years. Some of it is winter damage, and some is drought stress from last year. Most of these damaged leaves will fall off this season. Rake them up, and keep your shrubs watered this season if we don't get rain in a 10-day period.
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Rock-Rose
I just ordered some Helianathemum and now wonder if they will grow in our area.
If your area is Rhode Island or Zone 6, they should be fine; most are hardy to Zone 5. 
Rock-rose, as Helianathemum is commonly know, is available in more than one hundred species. Many are evergreen shrubs and the colors range through the spectrum. Flowers can be single or double and are very attractive against grayish foliage or dark green foliage. Rock rose can be trimmed after blooming to keep it neat and compact. These plants grow to about one foot high and will spread over time. Without trimming they tend to look a bit ragged. Helianathemum needs a sunny location and well-drained, alkaline soil. You will probably have to amend the soil. I found that they like sandy soil and they do very well on a south-facing slope where they get protection from winter. They thrive in dry rocky soils, hence the name.
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Snow Damage to Evergreen Shrubs
Heavy snows have made my evergreen shrubs spread and dip to the ground.  One large branch didn’t go back even after the snow was removed.  Is there anyway of retraining it?
This is a common problem in our Rhode Island climate; ice and heavy snows really take a toll on evergreens. If you are brushing the snow off with a broom after each snow you are doing a very good thing. As for your large branch, try propping it up from underneath. This is safer than trying to tie it up from above. Also, have you thought about establishing an inverted V-shaped snow barrier over your shrubs? Position it so the sun can get in an open side. My neighbor uses a pair of old louvered doors over his rather tall Alberta spruce because snow slides from the roof right onto the tree.
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Summer Planting of Perennials
I just bought some perennials and want to plant them even though its midsummer and the temperatures are in the 90s. Is this possible?
Although not ideal, it can be done. Plants that are purchased in containers can be planted almost anytime from spring through fall if certain precautions are taken. First, take care not to disturb the root ball any more than necessary as you set the plant into the ground. It helps to put some water into the planting hole first and let it drain out into the soil before planting. The same thing goes for filling the space around the roots: let the water take the soil down instead of packing it manually. Make sure the roots are well watered, especially so if the plant is in flower; water twice a day at the root level for the first week. Try shading the plant from hot midday sun using a screen or even some brush. Two window screens set up to form an inverted V will work well. Cut off any broken or injured stems. Remember that the plant needs to get acclimated and establish a good root system before putting out new growth.
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Sweet Pea
Why are the seedpods of my perennial sweet peas all twisted?
That’s the way they end up after dispersing their seeds. If you notice, as seed pods form the darker they get the more brittle they seem. All of a sudden the pods burst open in a twisting motion to send the seeds flying.
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Torch Lily
I planted some torch lily seeds last spring. The plants came up but never bloomed. My friend said they have to be planted in fall. When should they be planted?
Torch lily or poker plant (Kniphofia) is a perennial and, like most perennials, may take at least two years to bloom when planted from seed. During the first year the plant becomes established and develops a root system. Then in the following and subsequent years flowers appear. There are a few perennials that may bloom before the next winter if started indoors or in a greenhouse in late winter.

I hope you gave the crown, that is, the aboveground part, a good layer of mulch to protect it from being drowned, frozen, and heaved out of the ground during a hard winter. Some gardeners lift the crowns out of the ground, store them in moist sand, and replant them in spring.
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Tree Peony
I have a tree peony that didn’t do to well last year.  It was planted the autumn before so it should have been established. This is my first one so I really need some help.
Well, it was planted at the right time, that’s good. Tree peonies are really deciduous shrubs. They are descendants of Paeonia suffruticosa that have been grafted onto regular peony roots. The branches are hard wood compared to the soft stems of herbaceous peioies. They also demand a lot more care, especially when becoming established. Breeding nurseries usually hold these plants until their own root system has replaced the roots they were grafted to but occasionally some reach the garden centers prematurely. These will revert back to herbaceous plants very easily. Tree peonies need to be protected from hot sun and strong winds. This is really true in our Zone 6 during the winter months. Prune only to remove dead wood for the first six or seven years. They need to be planted deeply, about a foot at least, in slightly acidic soil and this should be done in the fall about 6 to 8 weeks before the first frost.
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Viburnum
The leaves on our lilacs and viburnums are curling up. Is this from lack of water? We live in Kent County where outside watering is restricted.
Yes, the problem is lack of water and it will only get worse during a long, dry and hot summer when watering restrictions are imposed. The day you can water, make sure you soak the plant root areas, and soak deeply. It’s the water pressure inside the plant’s cells that keeps the leaves from curling. When the roots can’t get enough water, the cell walls collapse. Eventually the stems will also be affected. Also, keep the root area mulched to help retain soil moisture.
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Winterberry
The landscapers planted shrubs at the entrance to our condominiums and now they have red berries. I'm told they are hollies but the leaves don't look like holly. Any idea what they are?
Yes, they are winterberry (Ilex verticillata), a native American holly. This is a deciduous holly that grows wild as well as being cultivated. The birds love the berries, which are produced on the female plants only and don't last very long. The problem is that deer feast on this shrub.
If growing conditions are right, winterberry can grow to a height of 12 to 15 feet and will spread into large clumps due to suckering. Winterberry likes swampy areas with acidic soils that are full of organic matter. They will tolerate partial shade but the best fruit set is in the sun. This is a very hardy holly that is slow growing but seems to have no serious problems. Many cultivars are available for home gardeners to choose from.
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Woody Shrub Removal
How do you recommend getting rid of trees of heaven? And do you know of a way to prevent sucker growth?
To get rid of a woody shrub use a woody plant herbicide to help stop new growth while preparing to dig out the dead plant. Replant two to three weeks after using the herbicides.

 

More Commonly Asked Questions:

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