The Good, the Bad and the Untidy: Thoughts on Early Spring

With spring upon us, many plants are already in full bloom and will soon require attention. Here are some answers to questions that may arise regarding seasonal plant care in your gardens:

What can I do about weeds already starting to sprout? Weeds that germinated in fall and winter, including chickweed, speedwell, henbit, peppergrass, shepherd's purse and yellow rocket, can be pulled by hand or with a weeding prong. Most will come out easily in moist spring soil.

It's the surest way to keep them from going to seed. Look for and pluck any weeds before they flower. Spread pre-emergent weedkiller to control spring weeds such as crab grass, or control them with corn gluten-based material, available at garden centers. These products are safe as long as you follow all labeled instructions.

What should be done to plants after daffodil and tulip flowers fade? Simply cut stems that held flowers, called scapes, to the base. It is not necessary to "braid" foliage.

Leave daffodils in the ground. Minor bulbs such as crocus, hyacinthoides and scilla will season without cutting the scapes.

Tulips are best dug as the leaves yellow and brown. Lay them in the sun to dry for about two weeks, protected by chicken-wire cages if squirrels, deer, raccoons and other wildlife are a problem. When bulbs dry, knock off soil and separate them. Place them in a porous bag with vermiculite to keep dry. Store in a cool, dry location until replanting in November.

Can perennials that were not cut back last fall be cut back now? If perennials have browned and died back from last winter, cut stems before new growth begins. Examples are liatris, verbena, chrysanthemum and black-eyed Susan stems. Cut liriope back to four to six inches, as well as ornamental grasses that have browned and died. Old leaves should be gone before plants begin putting out new growth. Use shears, a string trimmer or a mower on the highest setting.

Some winter and early spring flowering perennials don't need to be cut back. Some sedges, including leatherleaf ( Carex buchcananii) and evergreen sedges ( C. pendula), can be slow to renew, or not renew at all, if pruned. Also, don't prune bergenia, low mat-forming dianthus or winter-blooming hellebores, except to selectively prune browned leaves.

What care is required for forsythia, flowering quince and winter jasmine? Prune after blooming. Cut forsythia in half or to a height at which they will not need pruning again until after they bloom next year. Flowers form on the previous year's growth.

Flowering quince needs no pruning if it flowered well this year. When they display more wood than flowers, cut back to 18 inches.

Winter jasmine needs pruning only when it is growing where you don't want it. It can be cut to 12 inches after flowering. Planted over a wall or on a hillside, it is an interesting ground cover year-round. Renew only those plants that are overgrown and have lost ornamental value.

Should trees be fertilized now? Fertilize deciduous shade trees only if you didn't fertilize them last fall.

Use a general-purpose fertilizer that's not too high in nitrogen (in formulations of 5-10-5 or 10-6-4). Be sure it doesn't have weedkiller in it. Use five to seven pounds per 100 square feet on the area that's covered by tree branches. Follow label instructions. I prefer organic fertilizer with phosphorus derived from rock phosphate.

If there isn't any rain, water the fertilized area to help dissolve nutrients so they can get to the root zone.

What should be done other than fertilizing? Get organic material into the root zone of plants. Organic material helps tree roots retain moisture and nutrients. One inch of compost around the root system at the base of a tree is the perfect complement to fertilizer. Don't pile it against the bark.

Can I plant outdoor containers now? There's no need to wait until summer to plant containers, but don't plant annuals until after the last frost date, which is May 1 in this region. Use perennials, trees and shrubs in pots, urns or basins.

Be sure containers are large enough to accommodate several plants: 30 inches in diameter and 16 inches deep for one woody plant (Japanese maple, false cypress, juniper, or dwarf conifers) and three or four small perennials (creeping woolly thyme, lavender or liriope). Add annuals in May.

Container plantings require watering, fertilization, pest control and good drainage.

How can pests be repelled at this time of year? Insects are waking up now, and disease-causing organisms that were dormant in winter are emerging. Spray a dormant-oil insecticide or fungicide. Spraying now will ensure the least negative impact on the environment by reducing the need for more spraying during the growing season. If you don't want to use a petroleum-based product, make your own by mixing one cup vegetable oil and two tablespoons liquid soap (not dishwasher detergent). Slowly add one gallon of water. Use a clean sprayer.

What is the best deterrent for rabbits? Install low, inexpensive plastic or wire fencing around areas where they like to dine. Eighteen to 24 inches is tall enough, and when leaves mature, rabbits stop eating them. Home remedies include mothballs, dried blood, castor oil and cayenne pepper. Most have limited success and may need to be reapplied frequently.

What are some deer deterrents? Try protecting plants with a wall or a chain-link or deer fence. The latter is a rigid black plastic mesh that is eight feet tall and can be snaked around trees, through the woods, to be self-supporting. Other popular remedies include motion-sensor-activated water sprays, lights, sound devices, soap, and animal-based products such as egg mixtures or hair.

Another helpful solution is to use plants that deer don't eat. Possibilities include viburnum, nandina, magnolia, thorny holly, hellebore, rohdea, foxglove, iris, daffodil and catmint. Call your county or state Cooperative Extension Service (see http://www.csrees.usda.gov or http://www.hgic.umd.edu), or check with a local garden center for a list of deer-resistant plants.

What should be done to maintain tools and equipment? Clean, sharpen and oil shears, pruners and other cutting tools. Wash rakes, shovels and hand tools. Sand and oil wooden handles with linseed oil mixed with just enough kerosene to thin the linseed so it soaks into the handles. If you do this now, you'll be ready for the rest of spring.

Joel M. Lerner is president of Environmental Design in Capitol View Park, Md. E-mail or contact him through his Web site, http://www.gardenlerner.com.