Like other types of plants, perennials should be selected according to their cultural needs, and should be planted only where they can get the amount of sunlight and moisture they need, and where the soil is suitable or can be made so. An acid-loving plant in neutral or alkaline soil is a poor, short-lived thing; a moisture-lover withers pitiably where it’s dry as a desert most of the time; a “hardy” perennial won’t be hardy unless its environment is to its liking.
PLANTING AND CARE
Unless it’s utterly impossible, we do all our planting in the spring, so there is plenty of time for plants to develop vigorous root systems before a mean Connecticut winter comes along. This is particularly important to shallow-rooted perennials, and to any that are planted in windy, exposed sites. But for us, it also includes spring-flowering varieties. In spring we’ve planted dormant roots with or without mere nubbins of new growth, and plants that were fully leaved out and bursting with buds, with very little loss. But fall planting has proved to be a gamble; and if we’re forced into it, we’re more likely to find room in the cold frame for the new arrivals until spring.
Of course, this is not usually necessary in more temperate sections where plants set out in late summer and early fall have plenty of time to become acclimated before heavy frost. And it can be all wrong for Southern gardens, where planting during deepest dormancy is often recommended.
Even if you’re planting only three little pinks in a nook the size of a lady’s handkerchief, soil should be dug deeply and be suitably conditioned or enriched, drainage should be made perfect, roots should be spread out carefully, and watering should be as thorough as if you were planting a priceless miniature tree or shrub. To prevent a serious setback from wilting, put up some sort of temporary protection against sun and wind—an encircling screen of leafy branches, even a tent of newspaper or old sheeting.
Soil
There are few soils that can’t be improved by the addition of organic matter such as leaf mold, manure, or compost; and few plants that won’t grow better for it. It helps hold moisture in sandy soil, improves texture and increases drainage in clay-like soil, enriches ordinary garden loam. Mix it thoroughly with the soil before you place the plants. Also before planting, add lime to acid soil for plants that need it, acid peat for acid-loving varieties if your soil is neutral or alkaline. Above all, don’t plant anything (except for a few bog inhabitants) where water stands in puddles. Poor drainage has killed more perennials than Old Man Winter himself.
Watering and Mulching
Most miniature perennials naturally have rather shallow root systems, so they suffer quickly from drought. Don’t let them dry out seriously (particularly after transplanting); water often and deeply enough that the soil below the roots is wet. Thorough watering in late fall, just before the ground freezes, often makes the difference between winter-survival and winter-kill.
Mulching with any available, airy material—buckwheat hulls or crushed sugar cane, for example—will help keep soil moist and will also discourage germination of weed seeds, thereby saving you a bit of work.