Water wisely

By Katie Drewitz, U of M Extension

This year’s growing season is off to a fairly dry start in Central Minnesota. Your trees, lawn, and gardens may be noticing the lack of rain. There are a few things you can do to provide your plants with water while not compromising their health or root vigor.
For your flowers and vegetables, you should water early in the morning. This will allow the plants to take up water before the heat of the day. Night watering is not recommended. Watering at night increases your chances of fungal issues. If, however, it has been a particularly warm day and your plants are looking wilted, do not wait until tomorrow morning to water. In that case, night watering is better than not watering. You may consider using mulch around your plants. Mulch will help retain moisture in the soil as it protects it from the wind and direct sunlight. Mulch has the added bonus of suppressing weeds as well.
To encourage deep root growth in your lawn, it is best to water deeply and less frequently. If you continually water in small amounts frequently, the roots will stay very shallow. If you ever wish to stop watering your lawn, the roots will not be able to access water and the grass will die. Deeper roots can reach more water. If you are using a sprinkler system, be sure to test the system to ensure even watering. You should also consider having your system on manual control versus a set schedule. This will ensure that your lawn is being watered to encourage healthier root growth.
Container gardens will dry out more readily than in-ground gardens. Be sure to test soil moisture on a regular basis. For smaller containers, stick your finger in the soil to the second knuckle. Large containers and garden beds should be tested at the 6-inch depth. If the soil is dry, it is time to water. Soil type and plant variations will contribute to how quickly the soil becomes dry and how often watering is required.
Newly planted trees need to be watered daily for the first two weeks, three days a week for the next 12 weeks, and once a week until the roots are established. You can figure out how long it will take for the roots to establish and how much water your tree needs at each watering by measuring the trunk caliper. For a tree with a caliper less than 4 inches, take the measurement at 6 inches above the ground. For a tree whose trunk caliper is greater than 4 inches, measure at 12 inches above the ground. For each inch of trunk caliper, your tree will take 1.5 years to establish, and 1.5 gallons of water at each watering. As an example, a tree with a 4-inch trunk caliper will take 6 years for the roots to establish and will need six gallons of water per week for those first six years.
For more information on watering wisely, you can visit www.extension.umn.edu, or reach out to your local Extension Educator. Residents in Stearns, Benton and Morrison Counties can call (320) 255-6169 ext. 1, or email http://wins0115@umn.edu.