Timing is perfect for starting seeds indoors for annuals

It's not too soon to begin growing seeds of annuals that get off to a slow start, such as pansies, violas, snapdragons and lobelia.

While garden centers will offer many favorite flowers as transplants, when you start plants from seed the choices are seemingly endless.

Use grow lights to ensure success. A fluorescent tube fixture hung with hooks from chains works best, as you can adjust the position of the lights to keep them at the optimum 8 to 12 inches above the seedlings.

Providing bottom heat for the seedlings until they germinate will also improve results. Heat mats or cables can be purchased at your local garden center.

Once the seeds have sprouted and the seedlings have developed their first set of true leaves, thin them as needed to prevent overcrowding, keeping the best plants. When sowing, allow for a few more plants that you think you will need, but not too many.   

Winter is a good time to prune trees and shrubs. Overgrown deciduous woody shrubs can be pruning heavily this month and next to rejuvenate them.

Start by removing all dead wood and prune old canes off at ground level, leaving young canes. You may need to cut back the young growth too, if it is spindly.

If there are not any young canes present, cut the large canes back to 2 to 3 feet from the ground. This will be unsightly at first, but if the plants are healthy, extensive new growth should start from the old canes in spring and fill in the plant.

Shrubs such as lilacs that formed flower buds last summer will not bloom in spring when pruned aggressively in the previous winter.

Branches with interesting foliage as well as flowering branches can be forced. On a day that is above freezing, select branches that are not essential to the plant's basic shape or save branches from your winter pruning.

Branches for forcing should be at least 1 foot long and full of fat flower buds. Cut the ends of the stems at an angle and put them into water in a cool room out of direct sunlight. When the buds color up or the foliage begins to unfurl, arrange the branches in a vase and display them in a cool room out of direct sunlight.

Good choices for forcing this month include serviceberry (Amelanchier), magnolia (Magnolia), flowering quince (Chaenomeles), forsythia (Forsythia), crabapple or apple (Malus), flowering pear (Pyrus), flowering cherry (Prunus), spring-flowering witch hazel (Hamamelis vernalis) and redbud (Cercis).

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.