August is typically the hottest month of the year. If it is anything like the rest of this summer, anything can happen. We have had heat and humidity, drought and floods in between nights in the fifties and some of the most pleasant summer days in recent memory.

Drought has presented the biggest challenge to our lawns and gardens. Begin watering the lawn only if drought is prolonged. Once you do, if rain doesn’t materialize, you must continue watering with at least an inch a week.

In flower and vegetable beds, mulch consisting of woodchips, shredded bark, compost, straw, or even plastic and paper can help hold in moisture and reduce weed growth.

Watch for signs of insects and diseases. Japanese beetles seem to be out in numbers statewide. Commercial traps attract them from far and wide and are not recommended. Pesticide sprays can get rid of some of them. They lay eggs in lush lawns which seems like an unfair penalty for keeping your lawn healthy. The eggs hatch into grubs that feed in the soil for the remainder of this season and the beginning of next. Treating the grubs later is more effective than spraying the adults now.

Visit the UW-Extension Horticulture Team website at wihort.uwex.edu for the Wisconsin Garden Factsheet on Grubs in the Home Lawn.

There are several ways to get help from the UW-Extension with plant problems. The four southeastern counties provide Horticulture Help Lines. In Milwaukee County call 414-290-2410. In Waukesha call 262-548-7779. In Racine call 262-886-8451. In Kenosha call 262- 857-1942. You can now also visit the recently opened UW-Extension Horticulture Center at Boerner Botanical Gardens in Whitnall Park in Hales Corners, Monday through Thursday to get help with gardening problems.

From August 2nd through August 12th, visit the UW-Extension Master Gardeners at the Wisconsin State Fair in their “Model Backyard” exhibit in the DNR area. There is a native plants area, a butterfly garden, a vegetable garden, a working compost bin, a cactus garden and a rain garden sponsored by MMSD and the SouthEast Wisconsin Master Gardeners, Inc. New this year is the Lifelong Gardening demonstration area that features tools and techniques to make gardening easier despite physical limitations.

Numbers in parenthesis after entries in this month's garden calendar are for the UW-Extension’s InfoSource website (infosource.uwex.edu) where you can read, download and print over 200 messages on gardening and the environment.
 

First Week

The last date to sow sweet corn for the year is August 1st.

For late crops of beets, bush beans, carrots, Chinese cabbage, cucumbers, kohlrabi, and onion sets, continue sowing seeds until August 15th. Peas and collards can be seeded again now, too.

Aphids can continue to show up all season long. Dislodge them with a strong blast of water or use insecticidal soap (not dishsoap) when first noticed.

Continue controlling stripped and spotted cucumber beetles which spread bacterial wilt to cucumbers, squashes, melons, and gourds. Weekly dusts or sprays of rotenone, carbaryl (Sevin) or permethrin (Eight) are effective but only if insects are present. Apply late in the day after flowers close and bees are not present. Remove infected, wilted plants immediately.


Colorado potato beetle adults are back for a second generation. Since these distinctive, globular, yellow and black striped insects are so easily seen they can either be removed by hand or sprayed. A specific strain of B.t. called M-trak is effective against these beetles while they are still young. The insecticides carbaryl (Sevin) or the organic pesticide rotenone can also be used.

After the last raspberry harvest for the year, prepare for next year while also avoiding diseases by pruning out old flowering canes leaving only 3-4 young canes per foot of row. Wait until spring to prune back shoot tips.

Watch for the appearance of fall webworm webs on limbs of trees and shrubs. Cut out the tents or spray while the larvae inside are still young using the biological insecticide B.t. (Bacillus thuringiensis) sold as Dipel, Thuricide, or Bactur. Once the larvae are over 1 inch long control is not effective or necessary.

Avoid pruning trees and shrubs since doing so this late in the season can stimulate new growth that will not harden off in time for the cold winter weather ahead. Delay pruning until the end of the dormant season early next spring. Late in the season when trees and shrubs are going dormant, wounds heal very slowly. Tender wound tissue can also be killed by freezing temperatures.
 

Second Week

Harvest vegetables such as tomatoes and melons regularly and frequently to avoid
overripe fruit which attracts picnic beetles.

Harvest onions and garlic as the tops dry and fall over. Braid garlic tops and hang in a cool, dry place. Cut onion tops back to 1" and dry thoroughly before storing. Use any damaged produce immediately.

Fall bearing raspberries will begin ripening. Pick fruit as soon as ripe since overripe fruit attracts picnic beetles which will seriously damage fruit.

Make the second application of fertilizer on new plantings of June bearing strawberries. Apply 3 lbs. of 10-10-10 per 100 feet of row.

This is a good time to order and plant spring flowering bulbs for next year's early flower display. Plan for different flowering times to extend the season. As with most flowers, they are best displayed in masses of all one type and color rather than in mixtures which can be busy and garish.

 

Third Week

From now until September 20th is the ideal time to seed or sod new lawns or to repair diseased or damaged areas of your yard. For a new lawn, prepare area with an application of the herbicide glyphosate 10 days before seeding or sodding. Rototill the area to a depth of 6-8". Work in extra organic matter and fertilizer. Level and rake smooth. Rake seeded areas lightly to bury seed about 1/8 inch. Tamp to assure good seed to soil contact. Cover newly seeded areas with a very light layer of straw to help retain moisture. Do not allow to dry out until all grass has emerged - about 15 days. Mow as soon as the new grass is 3 - 31/2 inches tall.
    

To repair thin spots or damaged areas, core aerate first and then over seed. A slit seeder can also be used.

Seeds can again be sown for a late crop of leaf lettuce, mustard greens, Swiss chard and spinach.

If you haven't already done so, divide bearded irises now before their second flush of root growth which will occur during fall's cool, moist weather. Examine rhizomes for borer tunnels and soft rot. Destroy all infected plants. Replant by barely covering the small sections of rhizome each with a fan of leaves and some roots. Cut leaves back by 2/3's.
    

If you want flowering plants indoors this winter of fuschia, wax begonia, impatiens, geraniums, and coleus, root cuttings now in vermiculite or perlite. Use rooting hormone powder on cut stem ends. Keep flats or pots in a calm, shady spot outdoors until mid-September.
 

 Fourth Week

In the flower garden, continue deadheading which will allow plants to use energy reserves for a final flower display. If there are signs of diseases, remove all leaf litter and spent plants to prevent the spread of spores.

Prepare for a Labor Day fertilizer application to the lawn unless you will be doing a weed n' feed treatment later in September. Mid-September is the only time of year when weed and feed products are actually timed right for both the weed control and the fertilization. If you do three applications of fertilizer per year, they should be at Halloween, Memorial Day and Labor Day. Use a slow release product for the late season application.


Late season problems on deciduous plants should be of lesser concern than those that appeared earlier in the season since leaves will soon drop anyway. Diseased leaves should be removed promptly to minimize pest problems next year.