Sedums, sometimes known as Stonecrops, are great plants–they have nice flowers, they’re drought and heat tolerant, and they are beloved by bees and other pollinators.
The only downfall with them, in my opinion, is their tendency to flop over late in the season. One day you have a nicely rounded mound of plant and the next day it’s come apart, leaving two halves of the plant lying on the ground. Some varieties don’t seem as prone to this, but it is common with the most common types (e.g. the variety Autumn Joy). But there’s a very easy solution!
It’s “pinching back” or “tip pruning” the plants. When your sedums start to get some height on them, you shorten them, causing the plants to send out multiple shoots at each pinch point. This creates a bushier plant that will have more blooms and retain its nice rounded shape until frost.
This sedum (photographed in Niagara Falls, Ontario last week) wasn’t pinched back and already has flower buds. If it was mine, I would be pinching it back right away.
Here is one of my sedums–a dark variety whose name I lost a long time ago–with spindly stems that were ready to be pinched back last week:
I’ll show you exactly how I did it by focusing on this one stem:
I’m going to pinch the top of the stem off, about 4 sets of leaves down from the tip of the plant:
I use my fingers to pinch the stem off, as close to the next set of leaves as possible. You could use secateurs for this if you prefer.
And with one pinch, the stem is gone!
This is what the plant looked like when I was finished:
You can see another sedum to the right of it–it’s a different variety and is not yet big enough to be tip pruned.
And these are all the pieces I trimmed off of that one little plant:
In a couple weeks new growth will sprout and it will start to look like this:
The new green growth with turn as dark as the rest of the plant as it grows. Eventually, all of those new stems will produce flower buds.
A few minutes spent pinching back your sedums now will pay off later, both in more blooms and in plants that retain their shape. It’s a simple technique to help you have a fabulous looking garden.
Would you like to have more sedums? They’re very easy to grow from cuttings. If I was going to do that with the pieces I pinched off (above) I would trim off any flower buds and the bottom sets of leaves, leaving 2 or 3 sets of leaves in total, with some stem sticking out the bottom. I would let the cuttings sit out in a shady spot for a few hours so that the stems have time to callous over, and then stick them in the garden, up to the bottom set of leaves (i.e. don’t cover any leaves with soil–they will rot). The cuttings won’t get to be large plants this year, but they will start to grow and will get to full size in a couple years.
Bonus tip: I haven’t done this myself, but my friends at the Toronto Botanical Garden tell me that if you stagger the pinching back–say you do the front third of your plant this week, the middle third next week, and the back third the week after–you will be able to have your sedum in bloom for longer. The part you pinched back first will bloom first, then a week or so later, the next, and so on. I think this would look best if you had a few plants growing together in a swath.