Donna’s Garden Tips for August

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Treat bothersome yellow jacket nests at dusk if possible. These bad-tempered insects return to the nest in the evening so a more complete kill will take place. Spray with a generic wasp and hornet spray taking care to stand well clear of the nest. Occasionally a second application will be needed.

yellow jackets in nest

Yellow Jacket Nest

If you are planning to sow your lawn this fall, kill any weeds that are present at this time. Most herbicides require a waiting period before new seeds can be planted. Read the directions on you weed killer before spraying. Be sure and make note of the temperature guidelines. The effectiveness of most herbicides is determined by the temperature.

weeds in a lawn

Lawn weeds

If your blueberry bushes are too tall for convenient harvest, now is the time to prune off the tops of your plants. Additional thinning in February can also be beneficial to mature plants.

blueberry bush with ripe blueberries

Prune blueberries

Fertilize strawberries during August for next year’s harvest. Apply 1 1/2 lbs. of ammonium nitrate per 100 feet of row. Brush fertilizer from leaves to prevent burn.

rows of strawberry plants in a field

Fertilize Strawberries

Get fall transplants such as cabbage, broccoli and brussels sprouts in the ground. Keep them well watered.

person planting cabbage transplants in the ground

Plant Fall Transplants

Watch for large numbers of yellow ring necked caterpillars on blueberry bushes. Although the numbers can be alarming, the damage is minimal. Spray with liquid Sevin or spinosad or prune out the limbs with caterpillars and plunge them into a bucket of soapy water

bunch of yellow necked caterpillars on a blueberry bush

Yellow Necked Caterpillar

For control of grassy weeds in ornamental shrubs and flowers use a product containing Sethoxydim. This product kills grassy weeds such as wire grass but won’t harm most ornamentals. It can be found as Poast, Ornamec Over the Top, Bonide Grass Beater and Fertilome Over the Top. Read the label for list of ornamentals that it can be used with.

patch of grassy weeds

Grassy Weeds

bottle of Bonide Grass Beater

Bonide Grass Beater

Black spot on roses has been pretty bad this summer due to the frequent rain. Keep fallen leaves raked and bagged. This disease can over-winter in leaves that lie on the ground all winter.

red rose bush with blackspot on leaves

Blackspot on Roses

Frequent rainfall make regular mowing difficult. But, don’t wait too long to mow. The taller the grass gets, the more difficult the job becomes. When mowing tall grass you have two options: Set the blade high and mow more than once or attach a bagger and bag the tall clippings.

man push mowing tall grass

Mowing Tall Grass

Refrain from working in the garden when foliage is wet. You can inadvertently spread diseases from one plant to the other in the water on your hands and clothing.

garden plant in the rain

Wet Garden

Continue to harvest vegetables regularly. This insures continued production of your crops.

person wearing hat picking vegetables from garden

Harvest Regularly

Check mature tomato plants frequently for tomato hornworms. They’re difficult to spot but eaten leaves and excrement are pretty obvious. Pick off and kill unless they have been parasitized. Parasitized hornworms are beneficial and quit eating once they have been parasitized.

hornworm on tomato plant


parasitized hornworm on tomato plant

Parasitized Hornworm

Continue to water and fertilize squash and cucumbers and they will continue to produce through the fall.

cucumbers growing on a trellis


Trim leggy petunias and impatiens and then give them some liquid fertilizer such as Miracle Gro. They’ll look fresh and new in a couple of weeks.

flower beds of assorted colored impatiens


Refrain from mowing grass during dry spells. A little height on the lawn shades grass crowns during very hot and dry periods, preventing sunburn.

person push mowing lawn


Clean up fallen fruit from underneath fruit trees and grapevines. Many diseases and insects overwinter in dropped fruit.

apples on the ground under an apple tree

Clean up Fallen Fruit