Nancy Pollard
Cook County Extension
Horticulture and Environment Educator

Greenovations
Each month, staff from the University of Illinois will provide answers to commonly asked questions related to gardening, flowers, vegetables and home owner plants.

A. Consider allowing your lawn to go dormant in heat of summer.  While this practice seems to have lost favor, it was the only practice some decades ago.  Letting the lawn go dormant will be a huge savings in water bill, and your lawn will green up just fine when the weather gets cooler. 

Only be careful to keep the grass crowns alive.  The crowns just need just ½" water every other week to keep from dehydrating. The problem can be more severe in Use a rain gauge to chart it during hot dry weather.  Do not fertilize a dry or dormant lawn. Wait until around Labor Day before you fertilize again or do any renovation.  Our cool season grasses prefer to take the summer off.

If you want to coax your lawn into staying green during the heat of the summer, you can still save on your water bill.  Only water as needed, not on a schedule.  When is water needed? The grass will start to turn a bluish-grey, and the leaves curl or cup.  Catch it at this stage, and water, before it turns brown. If you step on the grass blades, they will not spring back as well. When the leaf edges starts to curl, that is the best time to water.

Water half an inch, measured by an empty straight-sided container, wait three hours and water an inch more.  Watering longer in one spot when it is dry, is often wasted, as it runs off rather than sinking deep to replenish the root zone.  Our clay soils only absorb 1/2" per hour. Wetting the ground first, then watering it well allows moisture to sink in better.  Watering deeply, encourages deep roots that can go longer between watering.  A sprinkle every evening encourages surface roots that will dry out quickly. Mow the grass high (Kentucky Blue 3") to encourage deeper rooting.

Large sprinkler droplets, low to ground conserves water.  Much better than a fine aerial mist that evaporates too much before it reaches the soil. Watering early in the day can also reduce water loss due to evaporation, and allows the blades to dry before evening, minimizing lawn diseases.  It is a myth that watering in the middle of the day will "burn" the grass. 

A. You are describing blossom-end rot. This disorder is usually most severe following extremes in soil moisture (either too dry or too wet). These conditions result in a deficiency of calcium available to the maturing fruit, at the spot where damage becomes apparent.

This happens when tomatoes are watered shallowly and often, or the soil in the container they are in dries out. The rapid wetting and drying of the soil inhibits the uptake of calcium – leading to blossom-end rot.  However, adding calcium is not the answer.  Even soil moisture is.  Mulch the soil area where the tomato roots are growing. Water deeply and less frequently to avoid blossom-end rot.  If your tomato is in a container, be sure the container is at least 5 gallons in size.  Don’t forget to have someone water while you are on vacation.

A. Many vine crops like cucumbers and squash have male flowers separate from  the female flowers.  Typically, they produce all male flowers at the onset of flowering and gradually start alternating male and female flowers. Only the female flowers have fruit.  Failure to set fruit early on may be due to lack of female flowers.  Be patient, and you will see fruit appear.