How and When to Divide Perennials | Expert Gardening Guide by STIGA

How and When to divide perennials

Learning how and when to divide your perennial plants is one of the best ways to keep your garden healthy and flourishing

Divinding your perennials encourages strong root systems, rejuvenates older plants, and even helps you expand your plant collection — or share a few with your neighbours.

Autumn is often the ideal season for this rewarding gardening task. In this guide, we’ll walk you through why, when, and how to divide perennials so they continue to thrive year after year.

Why divide perennials?

When to divide perennials

How to divide perennials: step by step

1. Why divide perennials?

Dividing perennials isn’t just about keeping your flower beds neat — it’s an essential part of garden maintenance. Here’s why:

Rejuvenation: Over time, perennial plants can become overcrowded and less vigorous. Dividing them gives roots more space and helps the plant regenerate, leading to stronger growth and more abundant blooms in spring.

Propagation: Splitting an overgrown plant allows you to create multiple new plants from one — saving money while filling your garden with more colour and life.

Relocation: If a plant isn’t thriving where it is, division gives you the opportunity to move it to a better spot with the right light, soil, and drainage conditions.

Benefits of dividing perennials

Dividing perennials brings many long-term benefits for both your plants and your garden. It keeps your plants healthy, saves money on buying new ones, and ensures your flower beds remain tidy instead of overcrowded.

It’s also a chance to refresh your garden layout — moving perennials to new positions where they’ll receive the right conditions to bloom beautifully.

2. When to divide perennials

As a general rule, divide your perennials in the season opposite to their blooming period. This timing allows the roots to settle and strengthen before they need to support new flowers.

Spring-blooming perennials (like irises or peonies) are best divided in autumn.

Autumn-blooming perennials (like asters or chrysanthemums) should be divided in spring.

Strong, well-established roots are better equipped to handle seasonal challenges such as frost or summer heat — ensuring your plants stay resilient year-round.

3. How to divide perennials: step by step

Dividing and replanting perennials might sound like a big task, but with the right approach, it’s simple — and the rewards are well worth it. Not only will you rejuvenate your plants, but you’ll also control their size, encourage more blooms, and get extra plants at no extra cost.

Step-by-Step Guide:

Dig up the plant entirely. Gently lift it from the soil, taking care not to damage the roots.
Loosen the soil. Use your hands to remove excess dirt so you can clearly see the root system.
Split the roots. With a clean, sharp knife or shovel, divide the plant into smaller, healthy sections.
Trim and replant. Remove any dry or wilted foliage, then replant the divisions promptly in their new spots with fresh soil and water thorough