For well over a decade now, I have been immersed in the field of horticulture. From studying plants during my academic career, working in the industry, or growing and caring for plants in my own time. In this span, I have always felt like all the excitement and all the anticipatory energy towards planting is devoted only to springtime. We need to break this narrative and give early autumn the credit it deserves for planting perennials!
What's so special about fall?
There are some clear exceptions to fall planting. Annuals for pops of color in the garden obviously need to be planted in spring or summer to get the most out of them before they die at the first freeze or frost. Warm season vegetables like tomatoes and peppers are also not going to be on the fall planting list. But for most of all your perennials- flowering plants, ferns, grasses, shrubs, or trees- September through October is a fantastic time to plant. This time frame is suited for our Hardiness Zone (6b/7a). Living in southern Alabama, I was more than confident planting up into early November and those in colder climates like Chicago may need to schedule their fall planting a bit earlier. A general rule of thumb is to plant about 5 weeks prior to your area’s average first frost.
Examples of fall planting at Yew Dell
Here at Yew Dell, the Garden Team is currently planting a wide variety of perennials, some fully-herbaceous and some semi-woody. Perennials such as Pink Evening Primrose, Stoke’s Aster, Blue-Eyed Grass, Hardy Garden Mums, and many more. Here’s why:
Getting these plants established in the ground at this time has many benefits to their health and overall vigor.
With night temperatures no longer exceeding 70 degrees, the chance these potted plants will have to endure any transplant shock is much lower. Despite still being a good 3-inches behind on rainfall this year, the temperate weather of autumn will help these newly-established plants be resilient. They will expand their root systems to find accessible water under such conditions, whereas a plant established in much hotter time may close the stomata on their leaves to limit water loss, shutting down the process of water uptake from the roots and putting the plant in a struggling stasis. Also with soil that is still quite warm from the summer, new plantings can establish their root systems prior to dying back for the winter. Then, come Spring, you have a plant that is quicker to promote stem/foliage growth and flower emergence because it already emerged from dormancy somewhat established in the ground.
Preparing to plant
As in the Spring, there may be some preparation you have to do in your garden bed before fall planting. This is a good time to remove leaf debris that has fallen from diseased plants during the summer. Adding a layer of mulch can greatly help too. Why not get outside in the tolerable fall weather to mulch your garden beds and get a head start on suppressing weed seeds? The same mulch layer that will help retain water next summer will be very useful in insulating the plants against the freezing temperatures and strong winds of winter. While adding a thin layer of compost into the garden bed below the mulch is perfectly fine for fall planting, adding granular or liquid fertilizer at this time should be avoided. You want the plant to get a head start but you don’t want to encourage it to rapidly grow and put on soft new growth that will ultimately be damaged by the cold.
There are so many reasons to give fall planting a try in your garden- especially with any plants you purchase at our annual Fall Plant Sale. We hope the next time you are preparing to do your yearly autumn bulb planting, you’ll consider a few perennials too!
Jeff Margreiter
Nursery & Greenhouse Manager