Have you heard that perennials spend half their life in a wheelbarrow? That’s because after a few years the clump either overgrows it’s allotted space or the center has died out. One of the coolest thing about perennials is their resiliency. While it doesn’t apply to every type of perennial plant, most of them can be divided quite brutally. You just chop the root ball into chunks with a large sharp knife or a shovel. This method is best used in fall unless you’re prepared to look at a less than perfect plant for the rest of the season.
Fall isn’t the only time you can divide your plants. You can divide from spring through fall, but not during the plant’s bloom time, and the simple method of just chopping them up with a shovel is definitely best reserved for fall when frost will soon ruin all the foliage and stems anyway.
One plant you don’t want to use the chopping method to divide is heucheras or heucherellas. These plants are tricker if you want to preserve what you have. I tried chopping a huge Heuchera apart once and wound up with nothing. Definitely not what you’re envisioning!
Technically, it seems that to split or to divide is not an interchangeable term. While they might seem the same, its both the plant and the outcome that makes a difference. To split – like firewood – is to chop apart. To divide is more involved and less brutal. Sometimes you need a more delicate, almost surgical approach. But this post is about general perennial division splitting. We’ll get into more complex methods another day.
In the video he’s talking about leaving some plants in pots over the winter. This gardener obviously lives in a mild climate, not just because of his discussing overwintering his pots, but the dead giveaway is the crape myrtles in the background behind the brown fence. Those aren’t hardy north of zone 6.
In the north, if you’re going to leave plants in the pot through the winter, bury them in the soil, making sure that you’ve nicely loosened it by digging the hole twice as wide as your pot and several inches deeper. If you leave potted plants sitting on top of the ground in zone 4 or 5 – they will freeze to death. In the ground they will have insulation, but only if you prep the hole properly. By loosening the soil several inches wider and deeper than the pot, when mid-winter thaws come along followed by plummeting temperatures again, the entire section of loose soil and the pot will move together as the ground expands and contracts. Use the same preparation to plant in the fall too, which can be done right up to the point that frost stays in the soil all day.
In this video below you’ll see how they’ve removed only a portion of a clump without digging the whole plant up. They don’t say what kind of plant it is, but it has a very shallow root system. You will find that some perennials that have formed large clumps will force you to dig the whole thing up to be able to cut through dense root systems.
Stay tuned for Part Two.