{ Posts Tagged ‘hosta’ }

When should I divide my perennials?

Yesterday was a gorgeous September day and I found myself out in the garden admiring my perennials–my mums have all of a sudden exploded with colour! Some of my plants, however, have gotten quite dense over the summer. A couple of my hostas are so huge a neighbourhood cat was sleeping under one the other day and I didn't even notice until it crawled out and gave me a sleepy “meow.”

What to do with my crowded beds? I haven't really had to divide anything until now (except my irises), so I wasn't sure when the best time of year is to do it.

I consulted Anne as I think I'd probably better get a move on if I'm going to divide anything before the first frost. Here is her advice:

  • The best time to divide most perennials is in early spring. This will give the plant time to get settled before the summer weather challenges arrive.
  • The second best time to divide most perennials is in early fall, when the soil is still warm and plants can get settled before winter arrives. Divide perennials about 6 weeks before the first frost.
  • Some considerations to think about; often the soil is too wet to dig in the spring when it is the ideal time to divide. Some experts also suggest that spring and summer blooming perennials should be divided in the fall, and fall blooming perennials divided in the spring. This means you are dividing non-blooming plants, which will have a better chance of survival.
  • Exceptions to this rule include bearded iris (August only), columbine (fall only), oriental poppy (early summer after flowering), bleeding heart (early summer after flowering) and peony (late summer).
  • Divide plants on a cloudy day. Water them well the day before the move. And water them well after the move.
  • Cover them if necessary to reduce wilting.
  • Take as much soil as you can lift from around the roots and replant immediately.
  • Use a garden fork or garden spade to loosen the soil and dig out the clump. An old, large kitchen knife, sharp garden spade or two garden forks are handy to divide the clump. Save the most vigorous sections of your clump from the outer edges to replant.

This information will find a place in my gardening journal. I also found this article written by Anne on dividing perennials, which I am going to print, along with the information above, for handy reference.