Tending to topiary
It’s hard to resist a little topiary tree, but keeping it alive can be a problem.
When we think about “decking the halls” for the holiday season, most of us envision traditional greenery such as boughs of holly, evergreen wreaths, and fragrant firs or pine trees. But in recent years, herb ornamentals and topiaries have become bright new stars in the holiday decorating lineup.
Now that December has arrived, you’ll be seeing them everywhere from grocery stores to upscale catalogs. And it’s difficult to resist fragrant rosemary shaped like a mini Christmas tree. Or a lavender “lollipop” standard (a shrub or herb grown with an erect main stem so it resembles a tree). Or an ivy wreath. Or a moss-stuffed, bunny-shaped frame covered with creeping fig.
The problem is, not many of us can keep these appealing plants alive long enough to ring in the New Year. According to experts, topiaries and other ornamentals are often doomed from the moment they arrive in the mail or come home from the store.
”Stick your finger into the first inch of soil to see if it is wet or dry," she says. "Better yet, pop the plant out of its pot and examine the roots for moisture. You’ll find most of them will be fairly dried out.”
It’s easy to understand why. It can take more than a year to get a rosemary or lavender large enough to prune. By that time, they are probably pot-bound and will get thirsty quickly.
Water the new plant thoroughly without drowning it, then check daily to see if the surface of the soil is dry. Most plants need a drink at least every three days. If you notice that the soil has pulled away from the pot’s edge, it needs water, pronto.
Ivy topiaries and other plants growing on frames stuffed with sphagnum moss also need to be watered regularly. In fact, if they are allowed to dry out to the point of wilting, they probably won’t bounce back.
Immerse a new, stuffed topiary in a tub or large bucket of water and hold it there until the water stops bubbling. Then move it to a waterproof spot until it stops dripping. Finally, place it on a piece of clear plastic where you want it to grow.
Topiaries growing on stuffed frames should be misted every day. And add a touch of diluted fertilizer to provide the nutrients mosses lack.
It’s also a good idea to spray or mist regular topiaries weekly to spritz away dust, deter pests, and add extra humidity to a dry, indoor environment. Or give them a quick bath in the sink or tub.
Pay particular attention to the undersides of leaves, where spider mites gather to begin their dirty work. (Ivy is particularly susceptible to mites. Spray with an insecticidal soap to deter them.)
You’ll also need to provide plants with the proper amount of light. Most topiaries, such as ivy, like fairly bright light, cool conditions, and good air circulation. East-, west-, and south-facing windows are all fine unless the sun is so strong it singes tender leaf tips.
Rosemary and lavenders crave bright light and will go downhill rapidly if stuck in a dark corner. Rosemary “trees” appreciate full sun, so make sure you have a suitable location before attempting to grow them. The foliage is very dense and without proper light, the tree will begin to rot. If interior needles start turning gray or black, immediately trim the bad bits out and turn the damaged area towards the sun.
Quick action just might save your rosemary from the trash pile.
Standards and trees should be moved one-quarter turn weekly to keep the shapes symmetrical. Feed every few weeks during the winter months with a diluted liquid fertilizer. And be sure to give regular haircuts when plants get scraggly, especially before stems get too woody to prune effectively.
At this point it may sound as if topiaries are too fussy to fool with. If so, Ms. Pierson has a less-tricky alternative: scented geraniums. “They’re great for beginners or anyone who has bad luck with houseplants,” she says. “They’re easy to grow and don’t have strict watering requirements like most standards. Best of all, they can provide plenty of flower power.”
Recommended varieties include Ginger, Lemon Crispum, and Angel. Be sure to start with a plant that has a strong central stalk.
While scented geraniums might be a good choice for the faint of heart, don’t completely rule out rosemary, lavender, or ivies. If you can provide the necessary indoor conditions, you should succeed. And mastering the care of these charming plants can be one of the nicest holiday presents you ever give yourself.