DIVIDE PERENNIALS
Digging up congested clumps of herbaceous perennials not only rejuvenates older specimens, but also enables you to increase your stocks of garden plants for free
Because soil holds on to warmth longer than air, September is a great time to lift, divide and replant some of your favourite herbaceous perennials. At this time of year perennials that flower in spring and early summer (such as hardy geraniums, Alchemilla mollis and hemerocallis) are perfect for division. These usually need dividing every three years. Later-flowering rudbeckia, heleniums and most grasses don’t like having their roots disturbed at this time of year. So, if you have any congested plants that need dividing, leave them until next spring.
How to do it
Lift the plants Using a spade, dig around the plant or clump you want to divide, and carefully lift it out of the ground, retaining as much of the root system as possible. Divide the clump Place it on an old compost bag to keep your path or patio clean and use the spade or a sharp knife to divide the plant into smaller sections, making sure that each piece has a good amount of leaves and roots. Plant up the sections Dig planting holes and enrich them with a little compost. Pop in the divided sections and backfill around the plants. Firm them in and water thoroughly.