Extension Educator, Horticulture
I usually don't have to give "the watering talk" until July. Unfortunately for gardeners June has brought July weather. Roger Swain once said, "Gardeners are just better waterers". There is a certain art to it.
As a general rule we say garden plants need about an inch of water a week, but that depends on soil, plants and how well the plants are established. A few guidelines may help. Clay soils tend to stay wet longer, but are harder to rewet once they turn to glazed pottery. Anything planted this year and any trees or shrubs planted over the last two years need extra water. New plantings and containers may need to be watered daily. Trees and shrubs purchased in containers will need additional water because of the container soils. Balled and burlapped trees may be able to go longer between waterings. Vegetables and fruit plantings need water especially when they are forming fruit. Even plants listed as drought tolerant will need extra water if just planted.
No one can give you an exact recipe on how much and when to water your plants because of all the variables specific to your yard. That's where the art comes in. It takes some practice to get to know your yard and garden. If you are not sure, dig down a few inches to feel the soil.
With lawns you have to decide if you want the lawn to stay green or just alive. The natural thing for cool season grasses such as Kentucky bluegrass is to go dormant when it gets hot and dry. They stop growing and turn brown. Once they have gone dormant, it's best to leave them there. Cycling between green-up and dormancy drains plant reserves. A dormant lawn doesn't look as nice and may have some warm season weeds come in, but is less prone to insect grub attacks. Generally the lawn greens up once we get into cooler, wetter weather.
The common question is how much water is enough to keep the lawn alive? Applying 1/4 to 1/2 inch every 2 to 4 weeks should be enough to maintain moisture in the stems and roots so the turf can survive and resume growing when conditions improve. Use empty tuna fish cans in area covered by sprinklers to determine how long the sprinklers need to run. Remember to mow lawns higher in summer between 2.5 to 3 inches and avoid applying excess nitrogen fertilizer during hot, dry conditions. Limit traffic on a dormant lawn.
Use soaker hoses to efficiently water landscape plantings. Slow watering is best. Use 3-4 inches of wood chip mulch to keep in moisture and reduce soil temperatures. Consider plants such as many native prairie plants that will tolerate drought periods once established. Water is one of our most precious of resources.
St. Joseph - Sunday June 12 from 2-5 pm sponsored by Village Gardeners. Meet at corner of Route 150 & Main Street between 1:30 and 1:45 p.m. to begin walk.
Decatur - Sunday June 12 from 11am-4pm tour public and private gardens. Sponsored by U of I Extension Master Gardens of Macon County PH: 217-877-6042.
Monticello – Saturday June 18 from 10 am – 4pm Garden Walk and Taste of the Garden featuring garden recipe tastings in 9 local businesses. Sponsored by Monticello Chamber of Commerce. PH: 217-762-7921.
Champaign – Saturday June 25 from 10 am – 5 pm. From small cottage gardens to grand country estates, enjoy Town and Country Gardens. New this year is shopping among garden vendors at Idea Garden (just south of corner of Lincoln and Florida Avenues in Urbana). Sponsored by U of I Extension Master Gardeners of Champaign County PH: 217-333-7672 or visit area garden centers for tickets. All proceeds fund Master Gardener projects including community gardens.