Watering tips, regimens for the urban gardener

As the weather improves with our warmer temperatures and nicer days, gardeners are planting and starting their watering regimens while yards and gardens are beginning to green up. The way plants are watered impacts our quality of life. Pesticides and fertilizers that can run off in soil and/or leach into the ground water are often the result of watering practices everyone uses. By applying sound water management principles gardeners can produce healthier higher yielding plants and crops, help minimize water contamination and runoff, and maximize water infiltration. 

Tips for responsible irrigation

Water when plants need it by filling the entire root zone and then letting the area dry out before the next application. Avoid frequent light irrigations since that practice encourages shallow rooting.  Also, be sure to avoid continuous watering as that tends to weaken plants and can create other stressors. Plant water requirements vary depending on the weather, soil type, and plant size, age, and species. You should water less frequently in the spring (and fall) than in the heat of the summer. Gardeners can consider using drought tolerant or native plants that require minimal water.    

Vegetables

Raising vegetables in our dry climate is sometimes a challenge since plants are generally very shallow rooted and can dry out quickly requiring absolutely necessary irrigation spring through fall. Don’t allow seedlings to completely dry out. If there is a choice, choose drip irrigation over sprinklers.  Where water is in short supply, consider using shorter season water users or plants that can stand short periods of water stress. Avoid over irrigation, monitor soil moisture and maintain fertility. 

Lawns

Lawns in the Columbia Basin may require water every other day in the heat of the summer depending on the soil type. However, at this time of year (and in the fall) when temperatures are lower, watering is not needed quite as frequently as it is later when it is warmer. Contact Grant-Adams Master Gardeners for free measuring cans and a written procedure to help determine the amounts of water yard sprinklers apply. 

Following good soil management practices like regularly aerating, dethatching, soil testing and applying fertilizer, and mowing can help improve the lawns drought tolerance. Adjust sprinklers to minimize runoff. Apply plant, plastic, bark, paper or fabric mulches to conserve soil moisture and control weeds. Try not to water lawn and landscape trees at the same time. Trees and shrubs require different methods and watering frequencies than lawns. Also, properly following pesticide and fertilizer labels can help keep the lawn healthier. 

Trees

Often stress in trees and shrubs are the result of not getting enough water. Be sure to water mature trees deeply, however do so infrequently. This practice will improve tree health and help prevent insect or disease infestations. Irrigating at or just outside the drip line to get water where most roots are located. Monitor moisture using a probe or shovel; the goal is to get good moisture penetration to a depth of about three feet.  

For gardening questions, contact the WSU Grant-Adams Master Gardeners at the WSU Extension office, (509) 754-2011, ext. 4313, or by email at ga.mgvolunteers@wsu.edu. For face-to-face contact or if you have a plant or insect sample that you would like to have identified, please visit our web page.