An easy, foolproof almost, way of getting more plants is to divide what you already have into smaller plants. This technique works on many clump or mat forming perennials that die back to a crown over the winter. I always thought that the right time to divide plants was when they are dormant, during the dark, cold months of winter. While there are some tough-as-old-boots plants that can withstand being rent asunder and replanted in cold wet ground, many won’t stand for it and losses are likely. I have had limited success with this approach in the past. Funnily enough helenium is one of the plants that should tolerate being mucked about with in the winter.
In fact there are three times of the year when plants can be successfully divided.
- Winter (for tough plants)
- Early spring
- Late summer
The timings are optimal as they are in tune with plants natural growth cycle, particularly of the roots. In spring and summer the plants are either getting ready to grow or are already growing well so are better able to recover from being dug up, split and replanted. The soil is also warmer and there is more daylight.
Since we’re in early spring here in the south of England, I’ve taken the opportunity to give it a bash.
I have a clump of helenium which actually is only a couple of years old, grown from seed the year before last. The original grouping was three plants. Let’s see how many I can get from those. Have a guess!
First job is to dig them up. Nothing too complicated about that, it’s a case of getting a fork in under the plant and levering it up and down, loosening the roots, moving the fork around the clump until it can be lifted.
The temptation is to dive in to the top of the clump with the fork and start pulling it apart. I watched a video recently which advised against this, to avoid damaging the shoots. Instead he advised turning the clump on its side and splitting it from there.
There’s more than one way to skin this cat, but the two fork approach is the one I like. Two forks, jammed in to the clump back to back. Then they just need wiggling backwards and forwards. I find that the action that provides the most leverage is to use the angle of the forks and push the handles together (rather than apart). The metal tines then push each other apart, taking the clump with them. But don’t sweat it, jiggling back and forth does the job. If I didn’t have two forks I’d probably have used a spade or even a saw to split the clump.
I kept going with the forks until the clumps were small enough to pull apart with my hands.
I took the tray into Propagation HQ (the shed) for further preparation. Some of the little clumps were tough to separate with my hands, the crown section was too hard. Fortunately there’s an easy remedy for this, an old bread knife, or saw in my case, does the job. Just chop em in two, aiming for shoots and roots in both sections. This seems drastic but is not traumatic to the plant. Mind your fingers…
As I was splitting them up I removed the old woody stems, bits of crown and roots, they have no further part to play.
Next, I cleaned the individual divisions. I found that parts I’d previously thought were one potential plant often became two when I cleaned the mud off.
I left them in a tray of water so I could catch the Calcutta Cup on the telly. Maybe I need a telly in the shed?
As you can see, the roots are extensive and would be a pain to pot up, so I’ve trimmed them to a more manageable size, just using my shed scissors. This should also encourage the plant into a burst of new root growth, same deal as pruning top growth.
I managed to fit nearly all of them into 7cm pots, with just a few needing a bigger 9cm pot. The smallest pot for the job is always the most suitable.
After all that mucking about, from those three original plants, I have a total of 34 new plants! Pretty good return on a couple of hours investment. No special techniques, equipment, potions or conditions were required. 34! From 3!
In theory, all those plants can be planted straight back in the ground, but I’ve potted them up and they can live in the greenhouse for a few weeks to recover from the trauma of my tender fork and saw treatment.
In the process of dividing the clump there was some collateral damage, a few shoots came away without roots attached. These are effectively mini basal cuttings, if a little smaller than usually recommended. Brucie bonus! I’ve treated them accordingly, placing them in cuttings compost. They’ll go in the heated bench to hopefully put on roots over the coming few weeks. It will also be easy for me to take basal cuttings from the larger group of divisions before planting them out. Crazy stuff. Propagation squared! I’ll do a post on basal cuttings in the next few weeks.
I’ve got an enormous old clump of astilbe which will get the same division treatment at some point, further adding to my oversupply problem….
I’ll be back soon with more propagation fun.