Regional Gardening Reports :: National Gardening Association

In the Garden:
Pacific Northwest
November, 2008
Regional Report

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The healthy root systems on these bedding begonia, geranium, and tropical hibiscus cuttings indicate they are ready to be potted up so they can spend the winter months on the windowsill.

Success with Cuttings

During the last decade, I've become fascinated with growing annuals and tender perennials in containers on my back patio. By September, the Mexican flame vine (Senecio confuses) sprawls over the paving, the fuchsia and coleus are bushlike in stature, and my angel's trumpets (Brugmansia) are the size of trees.

It would be daunting to bring these lush plants inside. We don't have a greenhouse, and many of the plants are simply too heavy to move. Instead, I take cuttings, root them in water, and overwinter them in a spare room.

Easy-Does-It Propagation
My quick-and-easy propagating method was born of desperation the first year I grew a 'Charles Grimaldi' angel's trumpet. I loved this plant above all others. Its silken trumpets are apricot-colored and exquisitely creased and folded into pale green calyces. By day, they hang beneath the leafy canopy, but at dusk, they flare upward and outward, releasing a sweet sultry perfume.

Because I couldn't bear to lose this treasure, I decided to take cuttings and hope for the best. With frost breathing down my neck, I hastily cut 6- to 8-inch shoots and stuck them into a glass of water. Within a few days, white spots began to appear on the stems, and roots soon emerged at these points.

Emboldened by success, I began rooting other soft-stemmed plants in water, including fuchsias, bedding begonias, and geraniums. I cut stems just below a pair of leaves, remove the lower leaves, and put the cuttings in glasses or bottles. The roots usually appear at the leaf nodes. After filling the containers with water to below the remaining leaves, I set them in a windowsill, away from direct sunlight. North-facing windowsills work well. Coleus roots in about a week and most others within two weeks. After several roots emerge, I transfer them to 4- or 6-inch pots partially filled with commercial potting soil. I add potting soil to within half an inch of the top, and water thoroughly.

A Winter Home
To accommodate the cuttings, we turned our guest room into a plant room. It has two south-facing and two north-facing windows. We turn the heat down and the temperatures approximate those of a cool greenhouse (55F at night and 65F during the day). A glassed-in porch where the temperature doesn't drop below 40F would also work.

If your growing space doesn't have enough light for sun-loving plants like angel's trumpets, you can improve the situation by installing fluorescent lights. I've found that shop-light fixtures with full-spectrum fluorescent tubes, suspended on chains so they can be raised or lowered, work well. Plant leaves should be at least 10 inches from the lights.

Ensuring Success
Here are two tips for growing plants indoors: avoid crowding -- plants need good air circulation -- and choose the right plants for the exposure. East, west, and south exposures are best for flowering plants, while foliage plants do best in a north-facing window.

Overall, I think temperature is less critical than light. The coleus, which needs less light and warmer temperatures than the room provides, suffers through winter in our plant room. It barely survives, but rebounds when I take it outdoors in the spring. Many other plants prefer it cool, and when the outdoor temperature goes above 40F, I open the window at the opposite end of the room. Plants like fresh air.

By early spring, my cuttings are strapping plants, and the sooner I can get them outside, the better. In April, and sometimes as early as March, I start putting the most cold-tolerant plants, like angel's trumpet and fuchsia, outside on the north side of the house. They get some early-morning sun, but it isn't hot enough to damage their tender leaves. At night, I bring them all in.

The indoor-outdoor regimen can be tedious, but it's worth it. You have to introduce these housebound plants to the outdoors gradually. Even sun-lovers must be exposed only to early-morning sun, at first. That's why the north side of the house is a perfect spot, because they get morning sun in increasing doses as the season progresses.

If all this sounds like a lot of trouble, it really isn't. During the cold months, I usually visit the plant room daily just to make myself feel better. There's not much to do, except pick off a dead leaf or two. In the spring, my garden gets a big head start; I've saved a bit of money, and I've had the pleasure of enjoying my favorite tender plants all year long.
