Snap, crackle, pop

Watering tips

Jennifer Fishburn,
unit educator, horticulture, University of Illinois Extension

[June 30, 2012]  It's that time of year again -- 90-degree-plus temperatures accompanied by the snap, crackle, pop of grass under your feet. If you think we get parched in the heat, how do you think plants feel?

Signs of a thirsty plant are wilting leaves followed by loss of leaves (the same signs apply to overwatered plants). Most plants will benefit from 1 inch of water per week to maintain plant growth.

During the summer months, watering lawns and landscape plants can account for 40 percent of a typical household's water consumption. Using water wisely in the landscape begins with the landscape plan and plant selection, followed by good soil preparation.

The key to developing a landscape plan begins with knowing the sunlight and soil conditions of your yard, and whether drainage is good or bad. Select plants that are suitable for the site and with low water needs, such as native plant species. Group plants with the same watering needs into the same planting beds. This will prevent overwatering of some plants and underwatering of other plants. Prior to planting, work the soil deeply, and if needed, add amendments to loosen. Composted yard waste or mushroom compost make good soil amendments. A well-drained, loose soil will allow plant roots to spread deeper in the soil to obtain water and nutrients.

Some more watering tips include:

Water early in the morning, before 8 a.m., or in the evening, after 6 p.m., and avoid watering on windy days. As much as 30 percent of water can be lost to evaporation by watering during the hottest part of the day. Watering in the evening can increase disease problems.

Most plants, including your lawn, prefer 1 inch of water per week. Depending on the soil type, 1 inch of water will wet the top 6 to 8 inches of soil. The frequency and amount of water applied is determined by weather conditions and soil characteristics.

A slow, thorough, deep watering is better than several light sprinklings. Deep watering encourages deeper root growth, which helps plants survive drier conditions. Lawn sprinklers, soaker hoses or drip irrigation add water to the ground slowly. Soaker hoses and drip irrigation systems are generally more efficient and cause fewer disease problems than sprinklers. Hand watering generally does not penetrate beyond the top 1 inch of soil; thus, you waste water and time.

Watering newly planted trees and shrubs should be your top priority. Flowers are easier to replace than a tree. Don't just water at the tree trunk; soak the entire area beneath the tree canopy because that is where the roots are growing.

Cool season turfgrasses, such as Kentucky bluegrass, can survive extended periods of drought by going dormant. Leaves will become brown, but roots and crowns remain alive for four to six weeks. If you do water your lawn, the best time to start is at the first sign of water stress: when footprints remain in the turf instead of leaf blades bouncing back. Once you have started watering your lawn, you must continue to do so.

To help conserve water use on lawns, mow higher, avoid traffic over the lawn, avoid pesticide use on drought-stressed lawns and do not remove more than one-third of the leaf blade at any one mowing. In the hottest, driest weeks, that means letting the grass get 3 1/2 inches tall before you mow.

Ground covers require less water than turfgrass. Consider replacing some of your lawn with ground cover.

Use organic mulches around your plants. Shredded hardwood bark, wood chips, composted shredded leaves and compost will conserve soil moisture, improve soil structure and moderate soil temperature. Mulch should be 2 to 4 inches deep and kept away from plant stems.

Reduce competition and stress to plants by keeping weeds, insects and diseases under control. Stress and competition increase the water demands of a plant.

For more tips on reducing water usage inside and outside the home, visit American Water Works Association at http://www.awwa.org/.

[By JENNIFER FISHBURN, University of Illinois Extension]