Dividing Plants: Boost Your Perennials, Bulbs, Tubers, and Succulents

Dividing plants is a satisfying gardening task that allows you to expand your favorite varieties. It's a straightforward method to fill your borders and pots with more of the plants you cherish, nurturing them from their offshoots.

This propagation technique is not only simple but also a vital strategy for maintaining a lush, vibrant garden.

By repeating beloved plants, you create a cohesive and appealing planting scheme, avoiding a chaotic mix of varieties. It’s advisable to establish a thoughtful color scheme for your garden.

“You can boost your collection of clump-forming plants—including perennials, spreading shrubs, rhizomes, bulbs, and tubers—by dividing them every two to three years,” explains a gardening expert.

Dividing plants helps keep them healthy by reducing overcrowding, promoting their vitality. Without division, some varieties may become less productive over time.

This practice also enhances the visual appeal of your garden. As perennials grow outward, the center can die off, resulting in unattractive gaps.

“It takes some time for the new plants to settle in, but you’ll save money and replicate the exact varieties you love,” the expert adds.

Plant Division Basics

Dividing plants means separating small rooted sections, clumps, or their tiny offshoots, bulbs, or tubers, and replanting them to grow into strong individual specimens.

Every plant has its unique propagation preferences. Some, like annuals, are best grown from seeds—essential for creating a cut flower garden.

Others root effectively from cuttings, such as rose cuttings, an invaluable skill for gardeners.

However, division is a straightforward and successful way to multiply many clump-forming plants, including:

• Herbaceous perennials—These non-woody perennials die back at the season's end but return each year, thanks to their robust subterranean root systems. Popular varieties include geraniums, delphiniums, lupins, peonies, rudbeckias, Japanese anemones, salvias, hostas, and various ornamental grasses.
• Clump-forming evergreen perennials—Many are still herbaceous but retain some or all foliage. Examples include hellebores and heucheras.
• Bulbs and tubers—This group features spring bulbs producing 'baby' offsets, like tulips and daffodils, alongside summer bulbs like alliums, agapanthus, and lilies. Dahlias are the most notable flowering plants with tubers, alongside certain orchids. Other bulb plants with corms, such as freesias, and rhizomes, like irises, can also propagate through division.
• Various succulents—Including aloe, sedums, and sempervivum.

Dividing Perennials

Perennials are among the most abundant plants and often feature prominently in your flower bed ideas.

According to gardening resources, perennials can be divided at nearly any time of year, provided they’re well-watered afterward. However, for the best results, do it while the plants are dormant.

Summer-flowering perennials should be divided in the fall before winter's chill or early spring when new growth appears, but avoid letting new shoots get too large.

Spring-flowering perennials are best separated in summer after blooming and when they start developing new roots.

Focus on those that have spread significantly and are becoming overcrowded, rather than smaller, newer plants.

“Look for large clumps pushing outward with fresh shoots at the edges,” advises a seasoned gardener.

1. To divide clump-forming perennials, use a garden fork to lift sections while minimizing disturbance to the rest of the plant—cut down through the roots and lever out the desired section.
2. These sections may need further splitting into smaller plants—aim for fist-sized clumps.
3. For plants with a closer-centered crown like hellebores, dig up the parent plant and carefully cut away new sections between growth buds, ensuring clumps have 3-5 healthy shoots.
4. Perennials with fibrous roots like hostas and heucheras can often be separated by hand—carefully remove them from the soil and tease apart the sections.
5. The newly divided plants can be placed directly into their new locations or potted.
6. Enhance the soil with nutrients, such as blood, fish, and bone, to support new plant growth.
7. Water thoroughly until established.

Dividing Dahlia Tubers

Dahlias need special attention during division due to their tuberous roots.

Understanding how to grow dahlias includes knowing how to overwinter their tubers. A common method is to lift and store them, as frost can be detrimental, making it the perfect time for division.

1. Once the foliage has blackened, cut it back to about 6 inches. Carefully dig out the soil and lift the tubers, avoiding cuts.
2. “You can either wash and divide the tubers immediately or store them in a cool, frost-free area until you’re ready to divide,” a gardening author shares.
3. “If storing, keep a light layer of soil on the tubers to retain moisture and prevent shriveling.”
4. Before dividing, wash the tubers and let them dry for a couple of days in a dry, frost-free location.
5. Once dry, split the tubers into clusters using sharp, clean pruners.
6. “Discard any tubers with broken necks, rot, or severe damage. This initial sorting helps in identifying viable tubers,” the author advises.
7. Ensure each tuber has a sturdy neck and a visible eye. “Eyes can be tricky to spot, especially right after digging when plants are dormant. Some varieties have obvious eyes, while others are nearly impossible to see.”
8. After dividing, allow the tubers to dry for a day before storing them in a dry place, preferably in a plastic container or bag.

Dividing Succulents

“Succulents are particularly simple to propagate through division, as clump-forming types produce offsets,” according to a gardening expert.

With many succulent varieties available, if division proves challenging, many also propagate successfully from cuttings.

• In many succulents, remove soil around the base, then gently separate sections, offshoots, or 'baby plants.'
• If roots resist separation, you can cut through them, and the plants will recover.
• Replant new succulents immediately in the ground or in pots filled with well-draining potting mix that preferably contains perlite.
• “You can also take leaf cuttings from fleshy-leaved species and stem cuttings from branching types,” the expert adds. Fleshy leaves can easily detach and will quickly develop roots.

Can Most Plants be Divided?

While many plants can be split, not all can. Some require propagation via seeds or cuttings.

Generally, most herbaceous perennials and bulb flowers can be effectively divided and will thrive as new plants.