April can be a busy month in the yard and garden. Winter annuals are still blooming, but soon it will be time to replace them. Lawns that were fertilized in February or March are green and lush, which means you'll have to mow more often.
STARTING TIME: It's not too early to start spring and summer annuals from seed. Use a fresh, sterile potting mixture. Some people are successful planting directly into the flower bed, but more often than not that approach doesn't work. It takes several weeks for seedlings to reach the flowering stage. By that time the winter annuals will have completed their life cycle and should be removed.
Rejuvenate the bed by raking out all leftover plant material and adding 25 pounds of organic matter (peat moss, compost, animal manure, etc.) per 100 square feet (a 10- by 10-foot area). You can also incorporate fertilizer at this time. Slow-release fertilizer will supply nutrients over a long period of time. Some formulas last for three months or more.
Plant caladium tubers to add color to your summer landscape. Tubers should be planted 2 inches deep in loose, well-drained soil. Caladiums' colorful leaves will lend a splash of color in shade or partial sun, and several strap-leaf varieties perform well in full sun.
FEED: Fertilize your amaryllis plants with a low-nitrogen fertilizer, such as 4-8-8 or similar mixtures. Apply one pound per 100 square feet of bed. Amaryllis need to grow all spring and summer if they are to form flowers for next year.
PRUNE: Azaleas should be pruned when they finish blooming. Even the dwarf varieties benefit from pruning, which stimulates new growth, eliminates legginess and produces a denser plant. Azaleas are generally fertilized four times a year (February, May, August and November). Those who missed the February feeding can lightly fertilize now to accelerate new growth, then do regular fertilizing in May. Use a fertilizer formulated for acid-loving plants.
Hibiscus plants should be flourishing, with new growth by now. Plants that were injured by cold temperatures should be recovering. There is still time to prune if you need to shape your plants. Hibiscus, which blooms almost year-round, should be pruned periodically to control growth.
SPRAY: Small fruit should be showing by now on citrus trees that have bloomed. Spray with neutral copper and malathion to help prevent diseases and insects from destroying the young fruit. These chemicals are compatible and can be mixed for a combination spray if you follow label directions carefully. Organic treatments with soaps and oils will also be effective if used properly.
Diseases such as scab and melanose must be prevented. Once they enter the leaf or fruit, they create a permanent blemish. Some fruit loss is caused by early disease infection. Rust mites and spider mites discolor the fruit and foliage, causing permanent damage. Aphids, white fly and scale are often troublesome, especially on new growth. Natural enemies such as ladybugs, lace wings and friendly fungus also help keep insects under control. If you have large populations of these predators, it is best to avoid any chemical pest control. Even oils and soaps can kill beneficial insects.
SWEEP 'EM UP: Most trees are now completely leafed out. Fallen leaves make excellent mulch or compost, but when pine needles and leaves fall on roofs, they hold moisture and may shorten the life of some roofing materials. Pine needles do not blow off the roof as readily as leaves. Both needles and leaves can clog gutters.
It may be necessary to sweep leaves from the roof and to clean gutters periodically. When used as mulch, both broad leaves and pine needles keep flower beds from drying between waterings and add nutrients as they biodegrade. Use the leaves for your benefit at no cost.
Magnolia trees are called broad-leaf evergreens, but they have to shed their old leaves to make way for new ones. These old leaves turn pale green or yellow and drop. Magnolia trees shed throughout the year, but major drops occur from April through July. Trees do not become entirely bare, but many homeowners fear that their tree is dying. You may have to rake up many bushels of leaves each week if you have a large tree.
All trees do not shed at the same time, so if your neighbor's tree looks better than yours, wait a few weeks. Your tree will have new leaves and theirs will be shedding. Occasionally a magnesium or iron deficiency will cause yellow leaves, but they have a distinctive pattern that can be easily identified.
Compiled by Pam Brown and Carol Suggs of the Pinellas County Extension Center/Florida Botanical Gardens. Questions? Call them at (727) 582-2100.