Dividing perennials not only improves their performance, it’s also a great way of making more plants for free.
Old clumps of perennials often end up with a bare patch in the middle, or simply produce fewer flowers.
Others are thugs that have outgrown their allotted space and seem determined to take over the border.
Astrantias can be divided in autumn
Some later flowering plants, such as asters, are best divided in spring when they are starting into new growth. It’s also worth delaying division if you garden on heavy clay that will be waterlogged over winter.
Hostas are easy to pull apart into smaller pieces
However, there are many perennials that can be split now in autumn among them sedum, primulas, hostas, astrantia and bergenia.
The secret to dividing perennials is to be brave. Dig up clumps with a fork or even a spade, getting all the roots out. It helps to shake off as much soil as possible so that you can see the roots clearly.
A knife may be needed to divide plants
Some plants, such as hardy geraniums will pull apart easily into smaller pieces. Others may need splitting by using two forks back-to-back as levers, or even by putting a spade into the roots and slicing through. Many hemerocallis varieties, which produce fibrous roots, will need this treatment.
Once you’ve split the plant up into smaller pieces, replant the youngest and most vigorous. These can be individual pieces or a small clump.
Hemerocallis roots can be difficult to divide
Take care to replant at the same depth as the original plant and firm in well. An application of a feed such as fish, blood and bonemeal is beneficial. Water them in and don’t allow them to dry out if there’s little rain.
Any spare plants can be used to fill up other borders or potted up and given away to family and friends.