UNIVERSITY PARK, Pa. -- Most plants can survive under periods of moisture stress, but the conditions needed to establish a new plant during a drought such as the one we face this spring are markedly different, says a horticulturist in Penn State's College of Agricultural Sciences.

"Establishing a plant depends entirely on its ability to get enough water from the soil to maintain minimum moisture levels in the plant and its roots," says Bob Nuss, professor emeritus of ornamental horticulture. "New plants need more water to develop the root system so it can expand into the surrounding soil."

Nuss says the survival of any plant hinges on the quality and water-holding capacity of the soil. Light, sandy soils and heavy, clay soils do not hold moisture well. During droughts, gardeners should mix organic matter into the native soil.

"The sponge-like nature of organic matter absorbs and holds water, while creating pores for movement of air and water through the soil," Nuss says. "Compost, peat, rotted sawdust or aged tree bark all can be used to improve soils."

Nuss recommends mixing four to five bushels of organic material into the top 8 or 10 inches of soil for every 100 square feet of shrub bed or garden area. "Make sure soil and organic material are mixed evenly," Nuss says. "Solid layers of organic matter will prevent water from getting to roots."

Under drought conditions, plants should not be stimulated into vigorous growth using fertilizer. A balance of soil nutrients will achieve the best results. To find out the levels of nutrients already available in your garden's soil, use a soil test kit. Soil test kits can be purchased at local garden centers or at Penn State Cooperative Extension county offices.

After planting, use a layer of mulch to retain soil moisture and reduce runoff from any rainfall. Mulches also maintain more uniform moisture levels by preventing rapid evaporation from soil surfaces. Make sure to keep all mulches from touching the plant stem.

"Mulches also help control weed growth," Nuss says. "Weeds are another source of water loss from the soil."

Nuss says improving soil and other conditions, and using plants known to be drought tolerant, will help gardeners establish a plot even during a drought.

###

Contact:

Jeff Mulhollem jjm29@psu.edu 814-863-2719 814-865-1068 fax