As your September garden bursts with late-season color from Sedum, Aster, Sunflowers, Zinnias, and more, hopefully you feel a sense of accomplishment for everything you were able to grow this past season. But even as you sit and pause to think about the spring and summer season, as always there is more work to do in the garden!
September is a big month for cold and warm regions alike; regardless of where you are, this month brings an abundance of cutting back, cleaning up, and planting. We call fall the “second season of planting” for a reason! We’ll outline September gardening chores for all regions and highlight tasks specific to hardiness zone.
September Gardening Tasks: All Regions
Weeding. Spend 1-2 hours per week keeping up with weeding in your garden. Diligent weeding helps prevent weeds from going to seed and also prevents disease in next season’s garden.
Stop pruning and fertilizing. At this point in the season, pruning and fertilizing only promotes new growth that most likely will not make it through the winter.
Repot houseplants if necessary and bring indoors. Place them by a sunny window that has good airflow and make sure to check for pests.
If you want annuals to self-seed, stop deadheading in September. Annual Poppies, Zinnias, Sunflowers, and more will drop their seeds and (most likely) come back next year.
Leave Echinacea, Sedum, Grasses, and Clematis alone to provide habitat and food for birds over the winter months. These blooms also add texture and interest to the winter garden.
Write in your garden journal. Take note of what grew well, dividing your gardens up into sections as it makes sense (containers, vegetable garden, annuals, perennials). This will be a big help when you are planning your garden over the winter months.
Start cleaning up plants as they fade. Cut back any perennial that is diseased or that has started to turn yellow, including Daylilies, Iris, Peonies, Bee Balm, and more.
Dig up/divide Daylilies, Iris, Hostas, and more in September if they have become overcrowded or outgrown the space.
As you cut plants back and continue to weed, top up mulch in all of your garden beds to provide a nice layer of protection for the winter months.
Plant cover crops. As you finish harvesting tomatoes, beans, zucchini and more, build your vegetable garden soil for next year by adding quick-growing cover crops. Plant Clover,Vetch, and Austrian Winter Pea as “green manures” to help build nutrients and get the soil ready for next spring’s planting.
Add perennials and spring-blooming bulbs to your garden in September. Perennials planted in the fall offer up bigger growth and often bloom in the first season. Bulbs like Tulips, Daffodils, Allium, and more need the overwintering period in order to bloom in the spring.
September Gardening Tasks: Zones 1-7
Watch for frost warnings and have a tarp or sheet ready to protect tender annuals like Zinnias,Cosmos, and more.
Dig up and store tender bulbs and tubers such as Dahlias, Begonias, Gladiolus, and more.
Direct-seed spinach, lettuce, beets, and carrots for a last round of winter crops.
Order spring-blooming bulbs like Tulips, Daffodils, and more. Refrigerate bulbs for 6-8 weeks to “force” the wintering over period they need in order to bloom. Plant outdoors (or in a sunny spot indoors) in the early winter.
September Gardening Tasks: More Work Now, Less You’ll Have To Do In Spring
The more you accomplish in the September garden means less for the early spring when you’re busy with the long list of to-dos to wake your garden up for the season. If you’re thinking of adding a pollinator garden to your landscape, try to prep the area and get as much planted as you can this fall. Come spring, the plants will be much larger and that area will be primed and ready to add in annuals and other varieties. The more weeding and mulching you do in September, the less weeds you’ll have to deal with in the spring. Take advantage of the gorgeous weather that September brings most of the country and get yourself in a great position to start next season off running!