When you think of planting perennial flowers, spring might automatically come to mind: birds creating a cacophony of noise, gusty breezes drying out the mud, and the excitement of new growth. But here’s a little gardening secret—fall might be the perfect time to plant perennials.
While spring planting is tried and true, there are some interesting benefits to be had if you wait and plant in autumn. If you want to get a jump on the following year, keep reading.
Why Plant Perennials in the Fall?
While spring bursts onto the scene with vigor, and I can’t wait to get outside and start playing in the dirt, autumn is actually my favorite time of year to plant perennials. There are a few reasons why fall planting makes more sense where perennials are concerned.
Cooler Temperatures = Less Stress
Fall brings with it cooler air and soil temperatures that are perfect for encouraging strong root development. In the heat of late spring and well into summer, plants can become stressed as they try to establish roots and deal with the scorching sun at the same time. In contrast, fall’s more moderate climate allows perennials to focus their energy on building a robust root system before winter sets in. The top growth slows down while the roots flourish in the soil, which stays warm even as air temperatures drop.
Rainy Fall Days Aren’t Just for Reading & Drinking Tea
Yes, they are, who am I kidding. But rainy fall weather means less time hauling the hose out every day. The soil is consistently moist more often, making it ideal for planting and ensuring new plants get a strong start. You won’t have to water as frequently as you would in the dry days of spring and summer.
Fewer Pests and Diseases
By the time fall rolls around, many garden pests have done their worst for the season. They’re winding down, which means your new perennials won’t have to face as many hungry insects right away. Because let’s face it, it’s incredibly discouraging to plant flowers in the spring and watch them get destroyed when the bugs show up for the season.
The cooler weather of fall means fewer bugs will be on hand, giving your plants a good, strong start. The cooler temperatures also ensure fewer chances of disease spreading among your newly planted flowers.
Jump-Start on Spring Growth
Perennials planted in the fall will already have an established root system when spring comes. Once temperatures rise, they’ll be ready to shoot up with vigor, often outpacing their spring-planted counterparts. This gives you a garden that looks lush and full earlier in the season than if you had started planting in the spring.
Lighten Your Spring Load
Finally, if you’re like many other gardeners, spring is one of the busiest seasons of the year. Between cleaning up the yard after winter storms, getting the vegetable garden in and cleaning up flower beds, it’s hard to find time to put in perennials.
Plant perennials in the fall and shrink your spring to-do list.
Perennials Are Often Cheaper in the Fall
My favorite reason to plant perennials in the fall is that I enjoy a good bargain. While spring nurseries overflow with bedding plants, fall is no slouch when it comes to the selection of perennials, too. Many garden centers stock a wide variety of perennials in the fall, often at deeply discounted prices, as they need to offload the rest of their plants for the year.
Naturally, not all perennials will be available in the fall. Generally, spring-blooming plants are the first to be offered for sale each spring and also the first to sell out. If you have your heart set on perennials that bloom in the spring, you’ll likely have better luck purchasing them at that time.
Keep in mind that fall is also a great time to get free perennials from friends and neighbors who are dividing theirs.
How and When to Plant Perennials in the Fall
Now that we know why fall planting rocks, let’s talk logistics.
Timing
Fall planting doesn’t mean waiting until the last leaf has dropped or the first frost is on the horizon. The best time to plant perennials is roughly 6-8 weeks before the first hard frost in your area. This gives the plants enough time to establish roots before the ground freezes. For example, in many northern areas, this means aiming for late August, possibly into early October.
Choosing the Right Spot
Just like in spring, selecting the right spot for your perennial is crucial. Make sure the planting area receives the appropriate amount of sunlight for the specific plant and has well-draining soil. This is especially important as the days are growing shorter. Fall is also a good time to add compost to the soil to give your perennials, new and old, a nutrient boost.
Planting Tips
Digging the Hole: Dig a hole that’s about twice as wide and just as deep as the plant’s root ball. This gives the roots plenty of room to spread out, which is what we want in this nice, cool fall weather.
Spacing: Make sure to space perennials according to their mature size. It can be tempting to plant things close together for an instant full look, but giving them room to grow prevents overcrowding down the road. Remember, they’re going to be much bigger next year; we’re just giving them a head start this year.
Watering: Give your new plants a good drink after planting, and continue watering throughout fall if rain is sparse. Remember, roots are still growing even if the top growth slows down (which it will in these cooler, shorter days), so keeping the soil moist is key.
Do They Need Winter Protection?
The question of winter protection depends on where you live and the specific perennials you’re planting. In general, fall-planted perennials are hardy and can withstand colder temperatures once they’re well-rooted. However, if you live in a region with harsh winters or unpredictable freezing and thawing cycles, you might want to add some extra protection.
Mulching
Speaking of protection, once the ground begins to freeze, apply a thick layer of mulch—around 3-4 inches—around the base of the plants. This helps insulate the soil, keeps temperatures more stable, and prevents the soil from heaving during freeze-thaw cycles. Straw, shredded leaves, or even pine needles make excellent mulching materials.
When to Wait Until Spring?
While fall is an ideal time to plant many perennials, there are some situations where it might be better to hold off until spring.
Tender Perennials
Certain perennials, particularly those that are borderline hardy for your zone, might not survive winter if planted too late in the fall. These include more delicate species like some varieties of lavender or tropical perennials that need a longer season to establish. In this case, waiting until spring ensures they have the warmth and time to set strong roots before facing their first winter.
Transplanting Mature Plants
If you’re moving a large, well-established perennial around in your garden, early spring might be better. Spring allows for an extended growing season, so transplanted perennials can recover more easily from the shock of relocation.
Dry Falls or Early Frosts
If you live in an area with particularly dry fall conditions or very early frosts, the window for successful fall planting may be too short. In these cases, your plants might struggle to establish before winter, making spring a safer bet.
While spring may be the season that gets all the gardening glory, fall planting offers some fantastic advantages, not to mention one more chance to wiggle our green thumbs. Cooler weather, abundant rain, fewer pests, and stronger root development all work in your favor. With the right plants and proper timing, you can set yourself up for a beautiful, thriving garden come spring—before your neighbors have even picked out their perennials.
So, grab your gloves, head out into the crisp autumn air, and get planting! Your garden will thank you with beautiful – early – blooms next year.
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