Master Gardener: February garden hints

• To keep Valentine flowers looking their best, always use lukewarm water mixed with floral preservative. Adding pennies or aspirin in the water won’t help. Keep the flowers in a cool location, out of direct sunlight. Keep them away from stored fruits and vegetables as produce emits ethylene gas that speeds flower maturation.

• Never fertilize to “jolt” a houseplant into active growth. Reduced winter growth is a result of short days and lower light intensity. Watch for a spurt of renewed growth late in February or early March as the days grow longer, then resume fertilizing, mixing your plant food only ½ strength. Apply only when soil is damp.

• Check houseplants for shiny, sticky stuff on leaf surfaces (honeydew from scale insects or aphids) or white, cottony bits on stems or leaves (mealy bugs). Isolate infested plants from others until you’ve controlled the problem. Discard badly infested plants.

• Look at summer bulbs you are storing for winter to make sure they are firm & healthy. Remove & discard any that are mushy or have soft spots. Premature sprouting is caused by temperatures that are too warm; shriveling is caused by excessively dry conditions.

• Late February and March are the BEST time of year to have large shade trees and fruit trees pruned.

Pruning paint is not needed when trimming trees at the proper time. If you want to paint the wound for cosmetic reasons, use latex, NOT oil-based paint in late spring or early summer after sap flow stops.

• Spruce up your home with a healthy new houseplant. If low light is a problem choose a snake plant, or a vining pothos or heart-leaf philodendron.

• If you see little flies that look like fruit flies on or near your houseplants, the plants are infested with fungus gnats. Fungus gnat larvae live on decaying matter in the soil, and are only a nuisance, not a threat to your plant’s health

To control fungus gnats in houseplants, allow the soil to dry longer between waterings. You can kill fungus gnat larvae by watering a special strain of bacillus thuringiensis called H-14 into the soil.

• Try starting seeds needing three or more months’ growth indoors under fluorescent lights; geraniums, coleus, impatiens,pansies and begonias. Most garden seeds need only six to eight weeks inside.

• Sprout alfalfa, onion, broccoli, or mung bean seeds at home to enjoy in stir-fry dishes, salads, and sandwiches. Grow them in a glass jar on your cupboard, then move them into bright light after a few days to green them up & improve their flavor and vitamin content.

• Once flowers fade on potted tulips, hyacinths, or crocus, throw them out. You are unlikely to ever get them to bloom well again, even outdoors. If you want to try planting them in the garden next fall, keep the leaves healthy as long as possible in a sunny window.

• Remove flowers of amaryllis as they fade, but leave the stems until they yellow & wilt. Treat remaining foliage as a sun-loving houseplant until it is warm enough to move the pot outdoors next June.

• Rejuvenate drooping roses by laying them flat in warm water & cutting ¾ inch off their stems. Keep them submerged several hours before transferring them to a vase of fresh warm water & floral preservative.

Resources: U of MN Master Gardener Calendars