July 2005

Edible

Water in fertilizer applied to vegetables. Applying fertilizer to dry soil can cause fertilizer burn. Water the fertilizer in with the equivalent of one inch of water. Vegetables need on average an inch of moisture per week. One inch of water is about 65 gallons of water per 100 square feet. Place a few straight-sided containers in the garden when watering with an overhead sprinkler. An inch of water in the containers is an indication your garden has received the inch of water it needs.

Water the garden early in the day (5am to 9am). Watering during the hottest part of the day can cause the loss of 50 percent of the water applied. Watering early allows foliage to dry, thereby avoiding the development of disease problems.

For a fall harvest, sow seeds in mid-July for:
beets- www.urbanext.uiuc.edu/veggies/beet1.html
cucumbers - www.urbanext.uiuc.edu/veggies/cucumber1.html
summer squash - www.urbanext.uiuc.edu/veggies/ssquash1.html
turnips - www.urbanext.uiuc.edu/veggies/turnip1.html
collards - www.urbanext.uiuc.edu/veggies/collards1.html
mustard - www.urbanext.uiuc.edu/veggies/mustard1.html
carrots - www.urbanext.uiuc.edu/veggies/carrot1.html
beans - www.urbanext.uiuc.edu/veggies/beans1.html
rutabaga - www.urbanext.uiuc.edu/veggies/turnip1.html

Keep the seedlings supplied with moisture during the hot summer temperatures.

Check your tomato plants for signs of leaf spot diseases such as septoria leaf spot or early blight. The yellow or brown spots occur on the lower leaves first. Remove the infected leaves to prevent further spread. For control of tomato diseases, plant your tomatoes once every three years in the same area, remove old tomato plant debris from the garden before planting, avoid wetting the foliage when watering and fungicides can be used, but should be applied before the leaves show spots or when the first fruit clusters develop.

Ornamental

Check your roses and other ornamentals for Japanese beetles. University of Illinois entomologists are predicting a bumper crop of these destructive insects this year. Adults are copper colored with a shiny metallic green head. They will skeletonize leaves during the day from 9am to 3pm. The beetles may be active well into August. Control by picking off the beetles by hand. Neem can be used for control, but numerous applications are needed and should be applied early in the infestation. Japanese beetle traps will attract more beetles than they control.

Keep your lawn green during dry periods by applying 1 to 1.5 inches of water per week. Water the lawn early in the day to avoid evaporation of water. Place coffee cans in the lawn to measure application rates. If you allow the lawn to go dormant, be sure to apply at least the equivalent of ¼ to ½ inch of water every 2 to 4 weeks to keep the grass alive.

Water trees and shrubs during hot and dry periods. It is especially important to water trees planted this growing season. Established trees will also need water if conditions remain dry. Water the entire root zone. The root zone area extends beyond the drip line or outermost branches of the tree. Avoid over watering trees, especially those growing in clay soils. Trees have died because of roots sitting in very wet soils.

Reduce algae in backyard ponds by reducing nutrients causing the algae. Do this by reducing the number of fish in the pond, the feeding of the fish and the fertilization of pond plants. You can also flush the pond and add new water, add a mechanical filter system or increase the number of aquatic plants to allow as much as 50 percent of the water surface to be covered. Avoid using algae reducing chemicals because injury to animals and plants can easily occur with misapplication.

Apply controls for grubs such as GrubEx or Merit now before damage occurs. It will take these insecticides three weeks to kill the grubs. Use insecticides if you find more than 12 grubs per square foot or if you had grubs last year. Water the lawn prior to application and water the insecticide in. Remember adult beetles usually lay their eggs in turf that is in full sun and well watered. Eggs will usually start hatching in late July. So if your neighbors do not water their lawns and you do, don’t be surprised if you have grubs.

Watch for leaf drop and leaf scorch on trees in hot, dry weather. Maple and ash trees are especially prone to dropping leaves when under stress from heat and drought. Leaf scorching occurs when the leaf tissue turns brown and dies. Scorching occurs on the leaf edges. Water is being lost from the tree faster than the tree can replace it. Watering trees during dry periods can reduce leaf drop and scorch.

Try the Knockout rose if you have had problems growing roses in the past. This rose is very hardy and extremely disease resistant. It has deep green foliage with a tint of burgundy and it will grow three to four feet high. In the fall the leaves turn a deep burgundy. The red flowers are produced all summer with orange hips for fall and winter display. There is also a “Pink Knockout” with bright pink flowers and a “Double Knockout” with double cherry red flowers.