There’s a conifer for almost any landscaping situation. They can be mixed into perennial gardens or foundation plantings. Some make wonderful hedges, shrub borders and even specimen plants. But sometimes you need to prune conifers to keep them looking their best and in scale with their surroundings.

Timing is important when pruning conifers. Spring is a good time to prune many of them. But within that, some recover best if you prune before new growth starts, and others do best if you prune just as the new growth is starting: With many junipers, false cypresses, yews and hemlocks, prune in early spring, before new growth stretches. That way the new foliage will cover up where you’ve cut so you’re not left all season with a plant that looks as if it just had a haircut. Pine, spruce and fir are best pruned just as new tips, the candles, begin to stretch in spring. All you need to do is nip back the shoots before the new needles form.

PHOTOS: © Richard Bloom

The ‘Prostrata’?spruce (Picea pungens) in the top photo is beginning to get too large for its place in the garden. Rather than remove it, prune it. The first step is to cut back the branches that are forming leaders. Click on the photos for larger images.

Next, shorten the longest side branches. Never cut the stem back to a point where there’s no foliage left. If you do, some, such as yew and hemlock, will leaf out again. But most won’t, and you’ll be left with lots of bare stubs. The spruce in the second photo still has a natural-looking form, but now it fits better in its surroundings and new growth will quickly cover the cuts.

For more information on pruning all kinds of plants, check out The Pruner’s Bible at right.

seed-starting rolls

Peat pots are a great way to start seeds, but you don’t have to go to the store to find biodegradable pots. Instead, cut cardboard tubes from paper towels and toilet paper to start your seedlings. Using scissors, cut the tubes into short pieces. Each toilet paper roll makes two pots (illustration A) and each paper towel tube makes four.

After cutting them, set the cylinders into a tray, as you can see in illustration B. If you set them so they touch, they’ll support each other as you water the seedlings. They also dry out more slowly when they’re set close together.

Then fill each pot with seed-starting mix, gently pack it down and sow the seeds. Later, as you plant the seedlings in the garden, break down the side of the roll so all of the cardboard will be buried underground. Just as with peat pots, if the edges stick up above the surface, they’ll wick moisture away from the roots.

Serious about seed starting? Check out the Sprout House and Location Station at right!

problem solver

Winter burn

Winter burn causes an evergreen’s foliage to die off. The most common cause is desiccation. See how the exposed half of the juniper at right is brown while the side protected by the fence is just fine? This is a classic example of winter burn. If the shrub is in a windy or exposed area, such as the southwest side of a building, sun and wind draw the moisture out of the foliage. Because the soil is still frozen, the plant’s roots can’t take in replacement moisture, and the dried-out cells die. Once it’s brown, evergreen foliage won’t come back. So in spring, when the branches start to warm up and become supple, prune brown areas back to the first green shoots. New growth will eventually fill in the bare areas, but you may want to replace unsightly evergreens that have been badly burned.

To keep moisture in the plant, apply an antidesiccant spray, such as Wilt-Pruf®. These sprays contain natural, waxy resins that seal leaves and needles and prevent water loss without damaging the foliage. Apply antidesiccants to an evergreen’s most vulnerable sides after the ground freezes. For especially tender plants, such as arborvitae, hemlock and yew, spray all the foliage. Broadleaf evergreens, such as rhododendron and holly, should also have all of their leaves coated, top and bottom. Spray when the temperature won’t drop below freezing for 24 hours. One coating lasts about two months in winter sun and cold, then needs to be reapplied for maximum protection.

saving sweet potato tubers

Instead of buying new sweet potato vines every year, try saving the tubers. Carefully dig the tubers, as the skins of freshly harvested sweet potatoes are delicate. To toughen their skins, lay them between layers of newspaper in a warm, dry area, like the top of the refrigerator, for two weeks. Then, store them in an open box, with a layer of dry sawdust or sphagnum moss on top, in a cool (55 to 60 degrees), dry, dark place. A heated garage or basement works well. Check the tubers periodically and remove any that become soft and mushy. Tubers can be stored for several months.

In spring, propagate new vines by burying three-fourths of the potato, pointed end down, in a pot of moist sand. Put the pot under fluorescent lights on a heat mat set at 75 to 80 degrees. Sprouts will develop; when they reach about 5 in. long, pinch them off the tuber and pot them up in potting soil. Grow the sprouts under the same lights until the threat of frost has passed, then move the small plants outside.

winter aconite
eranthis hyemalis

These bright yellow flowers poke through the soil just when it seems that winter will never end. Even though they look fragile, they’ll tolerate freezing temperatures and snow without trouble. Plant winter aconite tubers in early autumn in alkaline soil. A shady lawn or under shrubs where they can reseed and naturalize is ideal. You can even plant them in perennial or annual borders. The extra water in summer won’t hurt the winter aconite tubers.

Before you plant the tubers, soak them in warm water for 24 hours. They’ll plump up and send out roots faster after you’ve planted them. Winter aconite tubers don’t have an obvious top, but don’t worry about it. Just drop them in the hole and they’ll be fine. Just like grape hyacinth, winter aconite looks best when planted in masses.

TYPE Bulb SIZE 3 to 4 inches tall BLOOM Late winter LIGHT Part shade to shade SOIL Alkaline, moist, well-drained PESTS None serious HARDINESS Cold: USDA zones 4 to 7 Heat: AHS zones 7 to 1

problem solver

Cold damage symptoms

If you live in an area that experiences cold winter temperatures, you have likely lost a few plants to low temperatures. Here are some symptoms of cold-damage and some strategies for surviving the cold.

DIEBACK – Dieback is caused by severe cold and rapid changes in temperature. Woody plants, like privet, survive, but only the bottom part of the plant will leaf out in spring. The roots are hardy and the lower portion of the plant was likely protected by snow cover or leaf litter. Bud blast is similar to dieback, but the cold kills the flower buds of early spring blooming plants. This is common in Northern gardens with forsythia and rhododendron. For plants that are susceptible to dieback or bud blast, try insulating them from the cold by making a circle of fencing around the plant and filling it with straw or dried leaves. Or choose new plant varieties that can withstand cold temperatures without suffering any damage.

PUCKERED AND DEFORMED FOLIAGE – These symptoms occur when tender leaves are hit by a hard frost in early spring. This is usually only a minor cosmetic problem that won’t damage or weaken the plant; it just won’t look as good. You can remove the worst-looking leaves, but leave as many as possible so the plant can grow.

FROST HEAVE – Tap-rooted perennials, such as coral bells, are most susceptible to frost heaving. Other affected plants are Shasta daisies, blanket flower, garden mums and coreopsis. Alternating freezing and thawing near the soil surface pushes plant roots out of the soil. Tamp the soil back down or the roots will dry out and the plant will die. For plants that are susceptible to heaving, place an extra layer of mulch on top just after the ground freezes. You can also weigh them down with a brick.