Table of contents for Sun-Drenched Gardens
Do you have a low, sunny spot that never seems to be dry enough to dig? Don't despair. While wet soil can be murder on plants that demand great drainage, there are plants that prefer this unusual niche. You can also plant moisture-loving trees as a care-free way to slowly change the nature of the site by removing some of the moisture from the soil and by introducing shade. In nature, trees often shade moist sites, and there is a wealth of shade- and moisture-loving perennials, shrubs, and other plants that have adapted to these conditions. So planting trees in a wet site opens up a whole new world of planting possibilities. Another care-free option is to simulate a low meadow, as might occur along the banks of a stream that floods often in winter and spring, introducing some of the plants that are native to these areas.
The abundance of moisture in this type of site can also help some marginal plants to tolerate strong sunlight, because no matter how intensely the sun shines, the roots of plants always get the moisture they need. So, this is a good place to grow moisture-loving plants that adapt to either full sun or partial shade. Some of these include aster, bee balm, and small trees like dogwood and Japanese maple. Arrange plants according to height, with the taller ones at the back of a bed, and capitalize on differences in plant texture. For example, a background clump of tall, dusty pink-flowered Joe Pye weed partners well with the brighter pink flowers of shorter perennials like bee balm or astilbe. And the tall strappy leaves of moisture-loving yellow flag iris flatter any plant in its company, including ground-hugging bugleweed or the vivid colored leaves of sun-tolerant varieties of coleus.
As the seasons pass, you will undoubtedly discover that some plants like this niche so well that they prosper with little care. Where winters are mild, dainty, colorful, spring-flowering primroses often flourish. Put tall garden phlox to work filling the garden with color through the second half of summer. And annuals may surprise you by reseeding themselves and coming back year after year. If you plant spider flower or periwinkle, learn to identify the seedlings, which will often appear in late spring near where the parent plants grew the year before. On a cloudy day, thin the seedlings by gently digging and transplanting the volunteers to a moist place where you want them to bloom later in the summer.
Making a Garden
Naturally wet soil can be an ideal garden situation for adapted plants. The soil is often high in organic matter, and quite fertile as well. The only thing missing from wet soil is abundant air, and plant roots need air to survive. Without it, there is the danger of fatal root rot. So, as you envision a garden for a wet, sunny site, do plan to cultivate the soil with a digging fork before planting. If you must, wait for the opportunity to cultivate the soil in a season when it is somewhat dry, because digging wet soil often results in compacted clumps that reduce soil drainage further. Late summer and fall is the dry season in many areas, so this may the best time to create this type of a garden. However, nurseries usually offer the best selection of plants in spring. If necessary, buy your plants in spring and keep them in containers until the soil becomes dry enough to cultivate.
A Meadow Alternative
In nature, streams and rivers often scour open flood plains clean in spring, and then a variety of perennial wildflowers sprout, and annual ones germinate from seeds, turning the area into a meadow. A number of beautiful care-free plants will prosper for many years in this type of situation. Some are asters, blanket flower, lanceleaf coreopsis, garden phlox, goldenrod, Joe Pye weed, meadow rue, purple cone-flower, rudbeckia, and a few types of ornamental grasses, particularly switch grasses. As a bonus, you may be able to add late-season color to such a meadow garden by sowing annual cosmos from seed in late spring.
This type of meadow is typically mowed once a year, in early winter, after the plants have shed mature seeds, and the birds have feasted on them through the long winter. During the growing season, you can keep a wild-flower meadow area from looking unkempt by neatly mowing its margins. You can also mow pathways that meander invitingly through the meadow. Another way to make a wildflower meadow fit into an urban neighborhood by looking less wild is to install a decorative fence that sets it apart from the rest of the landscape.