Cutting back perennials is an important part of maintaining your landscape. Check out this advice on when, why, and how to cut back perennials.
Spring Is Best
Honestly, it doesn’t really matter if you cut back perennials in the fall or spring.
No need to scroll through the internet and look up every kind of perennial you have to see when it should be cut back.
In fact, if you did that, you’d quickly realize half the answers say fall and the other half say early spring.
All you really need to know is either time is fine, however spring is slightly better for the following reasons:
1. Less Labor- By the time the curse of winter is over, you’ll notice that there is barely anything left from last seasons perennials. Anything that is left, is extremely weak and can easily be pulled out or cut.
Cutting back in the fall is tougher since the old growth hasn’t had as much time to break down yet.
2. Root Protection- Leaving the dead stalks and foliage acts as natural insulation for the plants roots. This can be valuable added protection during colder winters or winters with less snow cover.
3. Birds and Wildlife- If you’re looking to help out birds and other wildlife then consider leaving perennials untouched until spring.
Many perennials such as Black Eyed Susan and Coneflower offer animals a food source. Even though the flowers look completely spent they are good sources of food.
4. Maximize Photosynthesis- For the most part, if a plant still has green, or foliage that is not completely dead, then it is most likely still benefiting the plant.
Daylilies for example have foliage that stay green very late into the season. This is providing energy to the root system. If you prune in the fall you run the risk of cutting short the plants energy supply.
5. Some Perennials Have Winter Interest- Some perennials, especially ornamental grasses, actually add value to your landscape during the winter months.
Some Reasons to Cut Back in Fall
Even though cutting back perennials in spring is best, cutting back in fall does have some benefits.
The main benefit is aesthetic. Plenty of perennials turn black, and can be unsightly. If you have garden beds in main focal points of your landscape consider cutting back those perennials.
Also, if you’re looking to ad fall color by planting mums, or asters for example, you will want to cut back perennials and do some other fall gardening chores to get the most out of these garden beds.
Another reason to cut back in fall is if you suspect you had any fungal or insect problems during the past season. A lot of these problems can overwinter in the dead plant debris so it’s best to cut back and remove the infected material.
How to Cut Back Perennials
1. Choose the Right Tool– You have 3 choices for cutting back perennials:
The manual way: This is when you use your hands to pull off the dead debris. This works best in early spring since the plant foliage is completely dead and pulling is easy.
Pruners: Using a good pair of bypass pruners will definitely do the trick. This can be the most time consuming method but will give you the most precision.
Hedge Trimmers: This is usually the fastest way to cut back perennials. A reliable hedge trimmer is a great investment if you are looking to save time maintaining your landscape.
2. Don’t Cut Off Basal Growth– No, this doesn’t have anything to do with Basal the herb.
Basal leaves are tiny little leaves that grow at the base of the plant once the rest of the plant has died back. This helps protect the plant during the winter months by providing it with added insulation.
3. Collect Debris– Don’t get fancy with adding the dead debris to your compost pile. The old perennial growth could contain fungus, insects, and seeds that could infect your compost. It is best to throw away or segregate this material.
Deadheading Is Different
Don’t get confused into thinking deadheading perennials and cutting them back are the same thing.
Deadheading perennials is when you remove just the spent flowers, where as cutting back perennials means your are cutting back the entire plant.
Deadheading should be done after blooms have faded. Cutting back the entire plant is done much later, either fall or early the following spring.
Check Out These Posts Next
Fall Gardening: Tips and Maintenance
Protecting Evergreens from Winter Burn
Annual Vs. Perennial: What You Need to Know
Follow Me
Join my free email list!
Lynn Eubanks says
March 1, 2020 at 12:36 amI live in Az in the desert and have shade in the summer and no shade in the winter…the result of trees losing their leaves
What can I plant in these areas?
Mark says
March 1, 2020 at 1:46 pmdo most herbaceous perennials die back during your winters? I know that aloes a agave are good choices for shade as well as columbine, primrose, begonias, and salvia.