What to Plant in August, Because Gardening Season Is Still in Full Swing

For most of the United States, the month of August signals the beginning of the end of summer (sorry, summer lovers!). It’s also a month that is typically accompanied by excessive temperatures and dryness: Across the board, the median temperature for the United States in August is between 85 and 90 degrees Fahrenheit. That’s hot, especially for plants! Gardens you planted in early spring are stressed from the heat and are most likely in need of some help to keep blooming until the killing frost later this fall. A late summer refresh typically involves cutting back dead blooms, digging out dead annuals, and pruning crispy foliage. This tidying up might leave you quite a few holes in your garden, but don’t worry — gaps will be easy to fill.

Just because it’s the end of summer it doesn’t mean that it’s too late to plant in the garden. In fact, many plants — such as spring bulbs and perennials — need to be planted in the late summer or early fall months, depending on your zone, in order to generate enough energy to bloom in the spring. Not to mention, it’s never too late to add some colorful annuals to your outdoor space! You’ll be able to find many of them on sale right about now, along with quite a few perennials. Herbs are also a great addition this month as they’re easily moved indoors once the weather turns chilly so you can continue your edible gardening long past the last days of summer.

Here are five fabulous options of things to plant in the hot, dry month of August.

Chrysanthemums are a fall staple, and can almost always be found on any list that cover late summer or early fall plantings. You’ll start seeing traditional fall mums at nurseries this month — but you’ll also be able to find many heirloom varieties available. For gorgeous, unique blooms try “Seaton’s Ruby” or “Moira”. If you’re feeling nostalgic, go for the traditional florist mums! You’ll get no judgement from me. 

Mums are wonderful in part-shade and are also perfect for container gardening. Some varieties will thrive in full sunlight, but be sure to keep an eye on the plant’s blooms. If your plant starts fading, it’s getting too much sun. However, if you choose to use them in container design, keep in mind that they need a significant amount of water to stay vibrant and lush.

Cleome plants are a bit of an oddity. They produce tall, spindly flowers with extra long stamens — a physical characteristic that explains the plant’s common name. You’ll find varieties that bloom in shades of whites and pinks. Cleomes are technically annuals and are easy to find at garden nurseries, even this late in the growing season. They don’t look like much at the beginning of the season and are typically passed over at garden centers for this reason.

Spider flowers are a great option if you are looking for a plant that’ll provide ample blooms throughout the hot days and into the chilliness of fall, all the way to the frosts. To ensure they keep blooming, cleomes need to be planted in full sun. If cleomes are planted in part-shade or full-shade, the lack of light will drain the energy from the plant and will keep it from blooming. You might also get a bonus: If you live somewhere with mild winters, your cleome plants might self-seed — meaning they drop their own seeds to re-grow in spring.

Once the temperatures have begun to cool off at the end of the month (and more so into September), conditions will begin to ripen to plant bulbs for spring. Of course, this depends on your agricultural zone, so do your research ahead of time. Sometimes it’s difficult to think about planning for spring when the month of August can be so miserable — but early planning can pay off. Remember, it is very important that the night temperatures be consistently 50 degrees Fahrenheit or less before you plant your bulbs in the ground. Anything warmer than that, and you won’t have any blooms come spring. 

If your garden can meet those temperature requirements at the end of August, plan on planting these bulbs soon:

• Tulips
• Daffodils
• Crocus
• Allium
• Anemones

If your area’s still too hot this month, keep these beautiful blooms in mind for planting during the month of September or later.

If you can get your hands on pre-grown herbs, jump at the chance! While it’s too late to start growing most from seed, there’s no reason you can’t plant a few of your favorites in your bedding garden or in containers. When picking which ones to plant, it’s best to choose herbs that can tolerate a lot of sun and a lot of heat. Look for plants that originate in the Mediterranean, which are great options for the August sun and heat. Here are some strong picks:

• Thyme
• Rosemary
• Basil
• Oregano
• Mint

The best part about planting herbs later in the summer is that you can easily bring them inside when the weather starts to turn cold. Even if you don’t have sufficient light to grow herbs indoors, you’ll have enough time to harvest what you need to store for the winter.  

If you didn’t take my advice about what to plant in July, you really should this time around! Now is the time to scour nurseries and garden centers for those expensive perennials you’ve been lusting over. Personally I love to buy all of the half-priced David Austin rose bushes and “Little Miss Kim” lilacs that I can find.

Whatever perennials you’re into, you’ll be able to find them at unbeatable prices. If you’re looking for plants that’ll take up a large amount of real estate in your garden but don’t want to drain your bank account, you should take advantage of the month of August to make your purchases.

Don’t be turned off if these perennials look a little worse for wear. After a winter of regeneration and energy storage they’ll come back tenfold in the spring.