March filled with anticipation, preparation for gardeners

March is the month when gardeners get excited. After a long winter, the warming days feel good and bring anticipation for the coming season. This a busy time for garden cleanup and dormant pruning.

Garden equipment

ŸSharpen tools and service power equipment. Good-quality hand tools that are well maintained will make gardening easier and will last for years.

ŸKeep pruners in good working order by regularly sharpening the blades. When putting the pruners back together after sharpening, be sure to tighten the centerpiece properly. If it's too loose, branches will wedge in the blades; if it's too tight, the blades will stick closed.

ŸUse an electric hand grinder to put a sharp edge on your spades. New spades do not come sharpened.

ŸTake your power equipment in for service before the shops get busy. The will ensure that your equipment will be ready to go when you are. Well-maintained equipment will perform better and last longer.

General garden care

ŸMost evergreens will not respond well to being aggressively cut back; a good rule of thumb is to avoid cutting beyond green foliage. Yews are an exception. They will respond to being drastically cut back into old wood. But be patient: It may take two to three years for the plant to fully fill back in. Complete this pruning before the new growth begins in early spring for best results.

ŸMarch is a good month to control insects such as magnolia scale with an application of dormant oil. Verify that you have a problem insect before pursuing any controls and avoid applying treatments to try to deter insects.

ŸWhen you apply dormant oil, the temperature should be at least 40 degrees and the forecast should include no chance of freezing or rain within the following 24 hours. Avoid spraying on windy days to keep the spray from drifting onto other plants. As with any product, be sure to read the label to make sure the plants you are treating will not be damaged by the dormant oil. If used properly, dormant oils can be very effective with minimal impact on the environment.

ŸCut back last year's perennial stalks and foliage and clean up garden debris this month. It is best to cut back perennials before they start growing to minimize any possible damage to the new growth. It can be hard to see new growth on ornamental grasses, so be sure to cut them back early in the month before consistent warm weather sets in. If weather has been warm and the grasses are growing, cut them at a few inches above the ground to avoid the new shoots. Be careful of any bulbs that may have started growing.

ŸI prefer to stay out of the garden when soil conditions are wet to minimize soil compaction. But stepping carefully, you can gently press back any perennials that have been heaved out of the ground over the winter. There is a greater chance in March of frost heaving by the freeze-thaw cycle, especially of recently installed plants that were not mulched last year.

ŸDon't forget to clean bird feeders regularly, as moldy seed can make birds ill. Remove old seed and debris and then scrub with a solution of 1 ounce of bleach to 1 gallon of water. Rinse well and allow the feeder to completely dry before adding new seed.

ŸIt is a good idea to shake hanging feeders when refilling them to dislodge any compacted seed. Dump out wet clumps of old seed and sweep hulls off platform feeders often between the more intensive cleanings.

ŸMonitor winter burn on broad-leaved evergreens such as boxwood, rhododendron and holly and needled evergreens such as yew and arborvitae. Winter burn affects plants that do not lose their leaves over the winter. Leaves turn yellow and then brown in response to specific weather conditions or to salt spray from traffic. They do not actually burn, but rather dry up. Symptoms of winter burn typically appear first in late winter and accelerate in early spring.

ŸVarious conditions can combine to cause leaves to dry out. Mild winter temperatures and warm winter sun prompt leaves to use water, which cannot be replaced through the plant's roots if the ground is either frozen or very dry. Winter winds also contribute to the problem.

ŸWinter burn is common after extremely cold and extremely mild winters, and in both cases it is exacerbated by lack of snow or rain in combination with strong winds and abundant sun.

ŸIt is best to wait until new growth appears before pruning out damaged areas to make sure the browned sections are completely dead. I have seen boxwoods that have an overall brownish cast in very early spring completely green up later in the season. In general, it is a good idea to plant broad-leaved evergreens where they will have some protection from winter sun and wind.

Houseplants

ŸPrune houseplants as needed and start fertilizing them as they begin new growth. This is a good time to repot them if needed.

ŸA white or yellowish crust near the drain holes of the pot or at the base of the pot indicates a buildup of salts from either fertilizer or hard water. Built-up salts can damage plants, showing up in brown leaf tips and margins. Flush out the soil with a heavy watering using plain water.

ŸContinue to care for amaryllis after their flower display. Allow all stems to wither before cutting them off at the top of the bulb, leaving the green, strappy leaves.

Keep the pot in a bright, warm location, out of direct sun. Water the plant as needed. The leaves will continue to grow.

When all danger of frost has past, take the pot outside to a location protected from afternoon sun. Fertilize the bulb every 10 to 14 days with a liquid 10-10-10 or 15-15-15 mix.

But you likely will find it much easier to purchase a new amaryllis than to get yours to reflower.

ŸTim Johnson is director of horticulture at the Chicago Botanic Garden (chicagobotanic.org).