September Gardening Checklist: Mid-Atlantic Edition

September is a transformative month in the Mid-Atlantic garden and one of the best months for planting. As the summer heat begins to fade, cooler temperatures provide a refreshing change, making it the perfect time to prepare your garden for the coming months. Whether you’re looking to plant late-season vegetables, prune your perennials, or prepare your garden beds for winter, September offers the ideal conditions to ensure your garden stays healthy and productive. This checklist will guide you through essential tasks to keep your Mid-Atlantic garden vibrant and thriving throughout fall and beyond.

September Gardening Checklist:

ANNUALS:

-Time to change out the garden! Replace spent warm-weather annuals with cool-weather annuals. This includes: flowering kale, Swiss chard, alyssum, and violas.

-Compost any of the discard , unless it shows signs of disease.

-Plant cool-weather annual transplants outside. Even though it’s warm out, it is still recommended to harden them off.

-Bring tropical plants back inside for the winter.

-Consider purchasing chrysanthemums and either plant them in ground or containers for seasonal color. They may need extra watering if they dry out.

BULBS:

-Dig up tender tropical bulbs and prepare them for winter storage. Cut back leaves, shake off soiled allow them to cure in the sun for a day. Pack in wood shavings or moss over winter.

-Dig up and pot bulbs to overwinter. Good examples are: Tuberous begonias, caladium, and calla lilies will grow will indoors.

-Stop watering amaryllis bulbs and let them go dormant for the winter.

-For a deeper dive into bulbs: A Guide To Planting Fall Bulbs

PERENNIALS + ORNAMENTAL GRASSES:

-Plant mums in containers or ground for fall blooms.

-Plant any new perennials now as temperatures are ideal.

-Change out any tired container plants. Add semi-evergreen or evergreen perennials to containers for foliage throughout the winter.

-Apply herbicide to continue to keep weeds at bay.

-Dig up and divide any perennials that you weren’t able to get to in the spring.

GROUNDCOVERS:

-Plant new groundcovers in areas where there has been decline.

-Now is a great time to plant any new groundcovers along edgings or other areas that need filling.

-Apply pre-emergent herbicide to groundcover beds to keep weeds from sprouting.

-Dig and divide crowded areas and transplant to bare areas.

-Here are are some great ideas if you are considering what to plant: Our 10 Best Ground Cover Plants

SHRUBS:

Plant new shrubs this month! Temperatures are ideal but make sure to water well to encourage rooting. Mulch around shrubs to conserve moisture and protect roots.

-Transplant any shrubs that need to be moved. If possible make sure to dig up and replant on the same day for best results. Water shrubs deeply the day before transplanting.

-Bring tropical or marginally hardy shrubs indoors for the winter.

TREES:

Go tree shopping! Planting most trees in September, especially spring-flowering varieties, is ideal.

-Deadhead crape myrtles to clean up appearance.

-Rake leaves and use them as compost. It is one of the best mulches you can get!

TURFGRASS:

Plant sod or seed lawns now! The exception is warm-season lawns, wait til spring for those.

-Rake leaves off lawn as wet leaves can encourage fungal and bacterial diseases.

-Use broadleaf herbicide if weeds are persistent.

VEGETABLES + HERBS:

-Compost vegetable gardens for fall gardening.

-Take herb cuttings indoors to grow during the winter months. Basil, mint and sage are great for windowsills. Parsley can be grown easily indoors from seed.

-Harvest the last of the tomatoes and bring them inside to ripen.

VINES:

-Bring tropical vines inside for the winter. Repot them and place them inside near a sunny window.

-Plant new vines in the garden. Place a support structure with it when planting, this way you won’t disturb the plant once it is well rooted.

With these essential gardening tasks checked off your list, your Mid-Atlantic garden will be well-prepared for the colder months ahead. September is all about transitioning and preparing, and taking these steps now will pay off with healthier plants, fewer pests, and a more productive garden come spring. Keep up with your garden maintenance, enjoy the cooler weather, and look forward to a flourishing garden next year.

Happy gardening! x