Drought stress from above average temperatures and lower than normal rainfall is beginning to take its toll on plants in area landscapes. Lawns, trees, shrubs, perennials and annuals alike suffer from drought and express symptoms including reduced growth, yellowing, wilt, loss of branches and leaves, or in severe cases whole plant death.
Recently planted specimens and containerized plants are particularly sensitive to drought due to limited root systems from which to draw water from the soil. Irrigating when rainfall is insufficient and using techniques that conserve soil moisture and reduce water loss will help protect your landscape through this critical time.
Here are some tips to help plants through times of drought:
The Inch per Week rule. If there is not an inch of rainfall per week, provide the difference through irrigation. But keep in mind that sometimes more than one inch per week may be needed to keep your landscape plants thriving depending on weather and your site.
Mulch conserves soil moisture by reducing evaporation. A blanket of mulch shades the soil and reduces soil temperature which helps to conserve soil moisture. Consider using organic mulches (bark, wood chips, leaves, cocoa bean hulls) that once decayed, benefit the soil in comparison to rocks. Apply a fresh layer of mulch to areas where it is thin and soil is becoming exposed.
Water deeply and less frequently rather than shallowly and more often. Soaking the soil deeply every few days rather than light waterings daily will help encourage roots to grow deeper and plants to be more drought resistant.
Water in the morning. Cooler temperatures, reduced wind and higher humidity in the morning help getting more water to soak into the soil rather than to be lost due to evaporation. Morning sun and rising temperatures also help promote foliage to dry quickly and reduce the risk of foliar diseases compared to evening waterings. But when plants are under severe drought stress watering as soon as possible minimizes further damage, regardless of the time of day.
Consider time saving methods to help get the job done. Soaker hoses and drip irrigation strategically placed in the landscape can be used alone or combined with programmable automatic timers connected to your water faucet.
Choose drought-resistant plants. Consider native and other plants which have greater drought resistance. Check the following website for a list of recommended drought-resistant plants: http://www.sustland.umn.edu/design/drought.htm
Direct limited resources to plants in most need of water. When time and water resources are limited, direct your watering efforts to plants with greater drought sensitivity. If possible try to locate such plants (i.e. containers) closer to the water source.
Source: University of Minnesota Extension Gardening Information
Jackie Froemming, University of Minnesota Extension, 218-824-1068, froem022@umn.edu