November 16, 2018

Horticulture Pro Tip: Plant Division

While not all plants require division, there are some perennials that should be divided every year or even every few years.

If you’ve ever visited Denver Zoo, you’ve surely noticed the beautiful, lush greenery all around you as you walked the property. And as any good green thumb knows, that kind of beauty doesn’t happen on its own. It’s all thanks to the TLC of our amazing horticulture team, and they’ll be sharing some growing and care tips from time to time right here on the blog.

First up, we’ll tackle plant division.

While not all plants require division, there are some perennials that should be divided every year or even every few years. The good news is that plant division isn’t as daunting as it may seem, and can require just a few simple steps.

One of the first questions gardeners will ask themselves is, “How do I know a plant needs to be divided?” Here are some telltale signs:

  • Flowers getting smaller
  • Plant seems congested and tangled in itself
  • Plant develops a hole in the center
  • Plant flops and requires more staking

You also may simply want to control the spread of a plant or to add additional plants through division. Whatever your reason, follow these tips for a successful division.

Choose a Cool Day

Dividing plants on a hot summer afternoon can be a challenge, especially for more temperamental plants. Pick a cool spring of fall day, but remember that dividing in the spring might sacrifice a plant’s flowers for the year.

Small Plants

Smaller growing perennials can be divided fairly easily by working from the outside of the plant clump with a good spade. Use the spade to remove sections that are growing out of control or to simply separate them for transplanting elsewhere. You should be able to do this without digging up the entire clump from the ground.

Larger Plants

If you’re working with larger plants of thick clump perennials such as Shasta daisies, daylilies or border phlox, you may need to lift the entire clump out of the ground. You can do this using spades or pitchforks to lift up from both sides of the plant. Once it’s out of the ground, you’re free to make divisions as you see fit.

Plant Care

When dividing plants, they are more vulnerable during the process. Be sure to keep the lifted portions moist and in the shade while working.

With this gardening skill easily mastered, you can open up your gardening palette to a whole new world of plants that you previously may not have considered. Good luck, and happy gardening!


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