Water Water Everywhere

For herbaceous perennials, the form taken by precipitation, the intensity and duration of the event that produces it; the amount that actually reaches the plants instead of running off, and the timing of the occurrence in relation to the life stage of the plant are the conditions that may mean life or death. The long, slow, steady rain that produces a soaking inch (preferably late Sunday night to avoid ruining a weekend!!) is an entirely different event than a twenty-minute torrent that produces the same measured amount but little effective moisture. Rain that occurs too frequently saturates soils, and the cloudy skies don't allow plants to dry. Drought conditions lead to soils that are almost incapable of being re-saturated by anything but consistent, small, slow amounts of water. This is particularly true of heavy clay. Snow cover, where it occurs, can be powder dry or so heavy that it breaks the branches of woody plants and rots the crowns of herbaceous ones-especially in soils that are not as well-drained as they should be. Snow also acts as an essential insulation for plants susceptible to damage from frequent freezing and thawing. And then there's hail. In locations where hail is a frequent occurrence, perennial plants should exhibit 'hail-buster' characteristics: fine foliage or leaves protected by waxy or leathery surfaces, flexible stems, tiny flowers. What can we control? We can add supplemental water to environments under drought stress-but only if we have water, and are allowed to use it. We can reduce humidity to a limited extent by encouraging air movement. But we can't turn the average annual precipitation into those soaking rains applied at just the right time, or turn 15 inches into 40 inches.