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Dividing a perennial hosta plant in the garden

September Garden Checklist – Welcome Fall! 

As your September garden bursts with late-season color thanks to Sedum, Aster, Sunflowers, Zinnias, and more, hopefully you feel a sense of accomplishment for everything you were able to grow this past season. The business of the summer season is slowing down, evenings are becoming cooler, and sunsets arriving earlier. As you sit and pause to reflect of your beautiful garden, there are a few things you can do to make it even better.

September is a big month for cold and warm regions alike. Wherever you live, this month brings an abundance of cutting back, cleaning up, and planting. We call fall the “second season of planting” for a reason – planting in fall will give your perennials a big head start on their spring growth, so be sure to make the most of this time! We’ll outline your September gardening to-do list below.

Ten Things To Do In Your Garden In September

1. Dig in! Add perennials and spring-blooming (fall-planted) bulbs to your garden. Perennials planted in the fall can establish healthy roots, resulting in bigger growth and earlier blooms in the first season. Bulbs like Tulips, Daffodils, Allium, and more need the overwintering period in order to bloom in the spring.


2. Make notes in your garden journal. Take note of what grew well, and areas where you’d like to make changes. This will be a big help when you are planning your garden over the winter months.


3. Weeding. Be sure to keep up with weeding. Diligent weeding helps prevent weeds from going to seed in your garden, and helps prevent disease in next season’s garden.


4. Stop pruning and fertilizing. At this point in the season, pruning and fertilizing only promotes new green growth that most likely will not survive through the winter.


5. Encourage annuals to self-seed. Stop deadheading in September and let the flowers go to seed. Annual Poppies, Zinnias, Sunflowers, and more will drop their seeds and, in the right conditions, can come back next year. The seeds also provide a treat to feed birds.

 6. Leave seed heads standing. Perennials include Echinacea, Sedum, Ornamental Grasses, and Clematis standing to provide habitat for pollinators and food for birds over the winter months. These also provide texture and visual interest to the winter garden.


7. Clean up plants as they fade. Cut back any perennial that is diseased and dispose of the trimmings in the trash, rather than your compost pile, to prevent the spread of the disease. Cut back yellowed foliage on perennials such as Daylilies, Iris, Peonies, Bee Balm, and more.


8. Divide and conquer perennials that spread. Dig up and divide Daylilies, Iris, Hostas, and more in September if they have become overcrowded or outgrown the space. Learn More: How To Divide Plants This Fall


9. Mulch. Adding a layer of mulch in your garden beds to provide a nice layer of protection to prevent soil erosion, add some organic matter to the soil, and protect plants from snow and ice over the winter months.


10. Plant cover crops. Build your 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.


The more you accomplish in September, the less work you’ll have to do in spring!

  • 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 and get yourself in a great position to start next season off running.

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