August Gardening To-Do List

In August, annual and vegetable gardens are winding down in the North. Some garden stands by the roadside in New England will already have pumpkins out for sale at the end of August. But in the South, there is plenty of gardening yet to do.

Regardless of where you live, as the worst of summer's heat exits, you'll have the opportunity to take care of some garden tasks that you might have been putting off. Find out what you should be doing in the garden in August, depending on your region.

All Regions

• Pick your spots to work outside. Anticipate heat waves and humidity, and get your work done on the days most pleasant for working outdoors.
• No matter where you live, you will probably still need to water the garden in August.
• Be on high alert for insect pests. These include—but are not limited to—thrips, tomato fruitworms, tomato hornworms, spider mites, chinch bugs, scale, snails, and slugs.
• The heat and humidity of midsummer bring with them plant diseases. Inspect your plants for any diseased foliage, and remove it. Dispose of it properly; do not put it in the compost pile where it can continue to spread disease to plants via the compost. Also, disinfect your tools, such as pruners, between each plant to avoid spreading disease.
• Keep up with your harvesting, as many plants will be producing now. Failure to harvest can slow down production.

Mid-Atlantic

• There will likely be extended heat waves in August in the Mid-Atlantic. Protect your investment in your plants by keeping them adequately watered.
• Keep an eye out for pests, such as groundhogs and rabbits, so they don't get to your harvest before you do. If you find controlling these pests too difficult, consider growing groundhog-resistant plants and rabbit-resistant plants next year.
• Keep those bargain-basement annuals (such as red salvia) you bought in July watered and pest-free, so they will be ready for use in fall plantings.
• Continue to mulch to cut down on watering bills and to keep weeds at bay.
• Ensure that your automatic irrigation system is working properly.
• Harvest herbs both for immediate use and for drying.
• Order spring bulbs.

Midwest

• The Midwest can still have scorching days and extended heat waves in August. Keep plants well watered.
• Harvest vegetables and berries regularly, so the plants keep producing.
• Avoid pruning shrubs after mid-August. You will only be inviting new growth that will fail to harden off in time for cold weather and thus might become damaged.
• Continue to mulch to maintain soil moisture and suppress weeds.
• Keep any annuals you bought back in July watered and pest-free, so they're ready for fall plantings.

Northeast

• The Northeast generally sees hot, humid weather at the start of August, so keep plants well watered. The second half of the month is unpredictable; sometimes it brings rainy periods during which you can cut back on watering.
• Keep annuals for fall plantings healthy.
• Harvest vegetables and berries regularly.
• Continue to mulch.
• Avoid pruning shrubs after mid-August.

Pacific Northwest

• The Pacific Northwest generally sees moderate temperatures and some rain in August. Water shrubs each week during periods when it doesn't rain much. Bud setting and berry production both are adversely affected by drought.
• As the crops of early summer peter out, replace them with fall crops. This is the time to put in "cole crops," for example. These include broccoli, cabbage, Brussels sprouts, kale, and cauliflower. August is also a good time to plant leafy vegetables, such as lettuce and spinach. 
• Fertilize summer-flowering bulbs, such as dahlias. But stop fertilizing perennials, shrubs, and trees.
• Plant autumn crocus corms.
  

Pacific Coast

In Northern California:

• Northern California usually has sunny, dry weather with moderate temperatures in August. Plan to water your garden regularly.
• Plant garlic for a spring crop.
• Regularly harvest ripe fruits and veggies.
• Clean up your rose garden through deadheading and pruning.

In Southern California:

• Expect warmer, dry August weather in Southern California, and water your plants regularly.
• Continue to mulch for weed prevention and water retention.
• Regularly harvest ripe fruits and veggies.
• Start planning your fall garden with cool-weather crops.
  

Southwest

• The Southwest still sees very hot temperatures and little rain in August. Ensure that your automatic irrigation system is working properly.
• Practice grasshopper control. There are organic insect soaps you can use to control these pests. Or try a homemade concoction, such as 1 part crushed garlic to 3 parts water, to make a spray you can apply wherever grasshoppers are a problem.
• To prevent sunburn on young perennials and succulents, furnish them with some shade. This is easiest to do when you are growing them in containers; move the containers around as needed.
• Cut back tomato plants to encourage fall production.

Southeast

• The Southeast typically sees hot weather and a fair amount of rain in August. Watch out for fungal diseases, which wet conditions can promote.
• Continue to apply mulch as needed for moisture retention and weed suppression.
• Divide overgrown perennials.
• Harvest summer crops, and start planning the fall vegetable garden.