Late Summer Gardening Chores and Maintenance

Welcome to This Month in the Garden!

As the days of summer begin to wane, late summer is a critical time for gardeners to prepare their spaces for the transition into fall. While the days are still warm, the subtle changes in light and temperature signal that it’s time to focus on garden maintenance. Here’s a guide to essential late summer gardening chores to keep your garden healthy and vibrant as the seasons change.

Mophead Hydrangea

Deadheading and Pruning: Late summer is the perfect time to deadhead flowering plants. By removing spent flowers, you encourage perennials like salvia, daylilies, daisies, and zinnias to produce more blooms and extend their flowering period. Additionally, pruning back overgrown shrubs and perennials not only tidies up your garden but also promotes healthier growth. Be cautious with late pruning, though, as cutting too much can stimulate new growth that might not have time to harden off before the first frost. Be careful with pruning hydrangea as not to jeopardize next year’s blooms. Only remove dead wood from the center of the plant and avoid cutting stems, as buds could already be forming on previous growth. The spent blooms can be removed, or enjoyed over the winter, and removed the following spring. If you desire deadheading, remove the dried flower head by cutting the stem just below it and just above the next set of leaves at an angle. The seed heads of perennials such as Echinacea (Coneflower) are a food source enjoyed by birds such as American Goldfinch and can also serve as interest until cutting back the plant later in fall. 

Echinacea (Coneflower)

Also, consider dividing and transplanting spring blooming perennials such as Daylilies and Iris that have outgrown their space. Dig up the parent plant with a spade and gently lift it above the ground. Remove any loose dirt from around the roots and separate the plant into smaller sections with a sharp clean spade or by gently pulling apart by hand. Each division should have three to five vigorous shoots and a decent sized rooting system. Dig the hole slightly larger than the plant, place level with the surrounding soil and maintain watering throughout the remainder of the season. Now is an excellent time as the temperatures cool and the timing allows for roots to establish before the first evenings of frost set in. A general rule of thumb is to divide spring blooming perennials in the late summer or early fall, and to divide late summer-fall blooming perennials in early springtime when new growth is emerging.

Daylily ‘Stella D Oro’ Late Summer

Watering: Even though temperatures may be slightly cooler, your garden still needs consistent watering. Late summer drought can stress plants, making them more susceptible to diseases and pests. Deep watering is essential to ensure roots remain hydrated. Continue watering until the first signs of frost are in the forecast.

Hydrangea Limelight Prime

Weeding: Weeds are notorious for thriving in late summer, often competing with your plants for nutrients and water. Regular weeding is crucial during this period to prevent them from going to seed and spreading further. Consider pulling weeds after a rain when the soil is moist, making the task easier.

Knock Out Rose ‘Radrazz’

Pest and Disease Management & Feeding: Late summer can bring a host of pests and diseases that target weakened or stressed plants. Inspect your garden regularly for signs of trouble, such as yellowing leaves, holes in foliage, or powdery mildew. Depending on the issue, you may need to remove affected plants, apply organic pest control methods, or consider natural remedies like neem oil or insecticidal soaps. By late summer, many plants may have exhausted the nutrients in the soil. Fertilize your garden with a balanced organic fertilizer to give your plants a much-needed nutrient boost. Focus on perennials, shrubs, and late-blooming flowers that will benefit from the extra nourishment as they prepare for the colder months ahead. Keep enjoying the garden as roses, some species of hydrangea and rejuvenated perennials continue to shine, while later flowering perennials including Montauk Daisy, Mums and Asters prepare to display their late summer-fall blooms!

Montauk Daisy

Harvesting, Planting & Composting: Late summer is harvest time for many vegetables, fruits, and herbs. Be sure to pick produce as soon as it ripens to encourage continued production. At the same time, it’s an excellent opportunity to plant cool-season crops like kale, spinach, and radishes, which can thrive in the cooler temperatures of early fall. With an abundance of garden waste, late summer is a prime time to enhance your compost pile. Add grass clippings, pulled weeds (avoiding those with seeds), and spent annuals to your compost. Turn the pile regularly to speed up decomposition, ensuring you’ll have rich compost ready for next spring.

Keep Enjoying the Garden!

Late summer gardening is all about balance and nurturing your plants through the remaining warm days while preparing them for the cooler months ahead. By staying on top of these chores, you can keep your garden looking beautiful and healthy, setting the stage for a successful transition into fall. Whether you’re deadheading blooms, mulching, or planting fall crops, the effort you put in now will pay off as your garden continues to flourish.