The Great Garden Divide
There are many reasons gardeners love perennials, but one of the best is that dividing your perennials gives you more free plants! Perennials are the gift that keeps on giving. Dividing your perennials not only adds more flowers to your yard. It also helps keep your plants thriving and healthy.
When to Divide Perennials
Perennials should be divided after they finish blooming, so they can focus on root growth. That means you should divide spring-blooming perennials in fall and fall-blooming perennials in the spring. But, besides dividing after blooming, how do you know when they’re ready to divide?
Generally speaking, your perennials are ready to be divided the year they have the best flush of blossoms you’ve ever seen. But, “best bloom ever” is sort of subjective and hard to measure since changes year to year can be pretty subtle. Here are the signs to look for:
Smaller, paler, and weaker blooms or leaves in the center of the plant.
A bald spot or donut hole with nothing growing in the center of the plant.
Plants that are really crowding their neighbours.
What Day to Divide Perennials
Divide your perennials on a day that is cloudy and overcast in early to mid-fall. Sun and heat stress isn’t good when digging plants out and exposing their roots; it makes them dry out quickly. If it gets sunny while you’re working, find a way to give your transplants some shade. If you don’t have an umbrella, you can drape an old sheet over a few tomato cages to create some shade.
Only work on one perennial at a time, so you don’t have a whole bunch of plants drying out their roots.
How to Divide Perennials
Get a sharp spade and then position it so the plant’s outermost leaves are just touching the handle; that’s the drip line. Sink the blade deep at the drip line around the plant.
Once you’ve gone all the way around once, you’ll need to start cutting underneath the root ball, as deep as you can, and then leverage the whole root ball out.
Pull the root ball out, and then get to dividing it into chunks. You can split your perennial either with a sharp spade or knife or by gently pulling apart tubers, corms, or bulbs. Medium to large plants may be split into four parts. You may need to divide large or old perennials into many more pieces. Make sure each division has some solid roots and a few pieces of foliage with it.
Before you plant your divisions into their new homes, do a quick inspection of the roots. Remove and discard any rotting or mushy parts.
Transplanting Perennial Divisions
Transplant your perennials into new homes or pots as quickly as possible to keep the roots from drying out. Dig holes to match the size of your new plants. Make sure to plant them at about the same depth as they were before.
Water your new perennials well. If we have a dry fall in Powell River, you may need some supplemental watering through October.
Last but not least, apply a layer of mulch over the root zone to protect the plant through the winter. This will help retain soil moisture and regulate soil temperature, which will protect the roots from freeze and thaw cycles. If you’re worried about your newly split perennials making it through the winter, you can give them a bit of extra protection through the first winter by wrapping them in burlap.
Start Adding Perennials to Your Yard
If you don’t have any perennials to divide yet, why not add a few new ones to your yard this fall? We’ve got plenty of perennials to choose from at Mother Nature, and there’s still lots of time to get some new ones planted. Next year and beyond, you’ll be able to enjoy your yard full of beautiful, effortless flowers. And in just a few years, you’ll be able to divide them and start filling up your flower beds for free.