Your yard's microclimates may influence what grows

By MARY COLLISTER

© St. Petersburg Times, published March 3, 2000

When we think about landscaping our yard, we may look at the entire yard as one environment. But every yard has a number of microclimates, each of which changes seasonally and through the years as the landscape matures. To put it in scientific terms, a microclimate is the atmospheric environmental conditions in the immediate vicinity of a plant.

This concept of multiple microclimates was brought to my attention when friends had two rather large oak trees removed from their yard. The loss of the tree canopies immediately changed the amount and angle of light hitting parts of their landscape. Wind patterns around remaining plant materials were also changed. As the landscape renovation begins, existing plant materials will have to be replaced with plants more tolerant of direct sun and able to withstand more wind. The impatiens that thrived under the protection of the canopies is already showing signs of stress from too much direct sunlight.

This points out the importance of understanding the different areas of the landscape. It also opens up being able to plant a variety of plant materials in our yards that we might not have thought were possible.

If your yard is covered by large trees, walk around at different times of the day and see where the sunlight penetrates the branches and what land is completely shaded. You might be surprised at the small pockets of sunlight that enable you to use those plants needing more sunlight. If you find your yard is completely shaded, you may want to have your trees trimmed to open them up and allow more light through. This might enable you to plant sun-loving plants in places you didn't think possible.

On the other hand, if the majority of ground is open to bright sunlight all day, you may want to plant a few strategically placed trees or large bushes. These trees may enable you to use more shade-loving plants in your landscape. Remember: Small trees do grow, and very quickly in Florida, so don't over plant. Although our large oaks are beautiful and offer ample shade, your situation may not need such a large tree. Some smaller shade trees include dogwood, Star Magnolia (which can be grown as trees or shrubs), peach tree, crape myrtle (shrub or tree form), or golden-rain tree.

Other microclimates can be caused by low-lying areas in a yard. These areas tend to get more frost, when and if we get frost, and also stay damper. These temperature and moisture parameters should have a direct influence on what you plant in these microclimates.

In addition to adding trees or shrubs for shade, there are a number of other ways to adjust microclimates. Hard surfaces such as a fence can reroute or cut down on wind. Using fill or berming soil can improve drainage and help moist areas drain better. Study the microclimates in your yard and you'll make more appropriate plant choices and have better luck with the health of your landscape.

Now is a good time to add to your garden.

If you're looking for instant color, these annuals will help you out: alyssum, celosia, cleome, coleus, cosmos, dahlia plants, dusty miller, geranium, impatiens, lobelia, marigold, petunia, salvia, sweet William, vinca, wax begonia or zinnia.

For more permanent additions, try some perennials such as African iris, blue salvia, day lily, gerbera daisy, pentas, shasta, or verbena.

Don't forget to add some edible landscaping. This is a good time to plant beans, beets, cantaloupes, carrots, corn, cucumber, green onions, eggplant, lettuce, peas, peppers, pumpkin, radish, squash, tomatoes and watermelons.

For variety, plant some anise, basil, chervil, coriander, cumin, horehound, lemon balm, marjoram, sage, savory, and thyme. You don't need a vegetable garden to grow these vegetables or herbs listed; tuck the plants in among your ornamental landscape plants.

For summer color try some bulbs; Amazon lily, Aztec lily, caladium, canna, clivia, dahlia bulbs, gladiolus, gloriosa lily, or zephyr lily.

Some outstanding flowering shrubs for our Florida gardens include azalea, bottlebrush, confederate jasmine and India hawthorne.

If planting new additions to your garden doesn't keep you busy, here are a few more chores: remove any cold-damaged growth from plants, fertilize landscape plants and lawn, spray scab-susceptible citrus trees, prune landscape plants that require shaping and size reduction, pinch out growing tips and old blooms of annuals to increase branching and flowering, watch for pests, use your oak leaves as mulch or in the compost pile and try your hand at air-layering shrubs and trees.

It's obvious the slow season in our gardens have passed and now is the time to get back outside. Try to do any heavy work before it gets too hot. Getting the garden in shape now will certainly pay off this summer.

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