July is an excellent time to divide certain perennials. Not only does this allow you to control the size of your plants, it also revitalises and multiplies them for an even more colourful garden. Here are three perennials you should divide in July to ensure that they continue to flower brilliantly into autumn.
1. Iris
Irises are hardy plants that thrive in many types of soil and climate. Dividing irises in July gives them time to recover before the first frosts, ensuring that they will flower magnificently the following year.
Why divide irises?
Rejuvenation: After a few years, irises can become overcrowded and less floriferous. Division rejuvenates clumps and stimulates flowering.
Propagation: This is an effective method for multiplying your plants and embellishing other parts of your garden.
Plant health: By dividing irises, you reduce the density of rhizomes, which improves air circulation and reduces the risk of disease.
How do I divide irises?
Step 1: Carefully dig up the iris clump with a spading fork.
Step 2: Separate the rhizomes into sections, making sure each section has at least one leaf and healthy roots.
Step 3: Cut the leaves back to a height of around 10-15 cm to reduce transpiration and facilitate recovery.
Step 4: Replant the iris sections at the same depth as before, spacing them 30-40 cm apart.
2. Daylilies (Hemerocallis)
Daylilies are extremely hardy perennials that flower spectacularly throughout the summer. They are ideal for borders and beds.
Why divide daylilies?
Improved flowering: Dense clumps can become less floriferous over time. Dividing daylilies stimulates new growth and better flowering.
Pruning control: If left to their own devices, daylilies can overgrow their space. Division helps maintain a manageable size and shape.
Propagation: Multiply your daylilies to create masses of colourful blooms in different parts of your garden.
How do I divide daylilies?
Step 1: Water the clump well before digging it up to make the operation easier.
Step 2: Use a spade to lift the whole clump and separate the roots.
Step 3: Divide the clump into sections; each section should have at least three buds.
Step 4: Replant immediately in well-drained soil and water generously.
3. Perennial Geraniums
Perennial geraniums are popular plants for borders and beds because of their long flowering period and low maintenance.
How do I divide perennial geraniums?
Step 1: Water the plant well before digging it up.
Step 2: Use a spading fork to lift the whole plant.
Step 3: Divide the plant into several sections by hand or with a clean knife. Each section should have roots and buds.
Step 4: Replant immediately in compost-enriched soil and water well.
Dividing irises, daylilies and perennial geraniums in July can revitalise your plants, encourage abundant flowering and extend the beauty of your garden into autumn. By following these simple steps, you can enjoy a blooming, colourful garden for as long as possible, while preserving the vibrancy of your flowers.
