Dividing and Transplanting Perennials: A Simple Guide for Healthy, Thriving Gardens
Boost your garden’s health and save money by learning the best techniques for dividing perennials, rhizomes, and tubers
Any seasoned gardener will tell you, some of the best plants are the ones you can divide. Dividing perennials is a budget-friendly way to grow your garden—and more importantly, it keeps your plants healthy. Over time, many perennials become overcrowded or tired, showing signs of poor growth or fewer blooms. Dividing them gives the roots more space and stimulates fresh, vigorous growth.
Digging In to Transplant
There’s something deeply satisfying about digging into your garden with purpose, hands in the soil and shovel at the ready. Transplanting perennials isn’t just maintenance—it’s an act of renewal. Whether you're rescuing a crowded clump or spreading your favorite bloom to a new corner, every scoop of earth holds the promise of a thriving, refreshed garden. It’s a time to slow down, tune in to your plants, and get reacquainted with the roots—literally. With the right tools and a little know-how, dividing and replanting becomes one of the most rewarding (and budget-friendly) ways to grow your garden from the ground up.
When Should You Divide Perennials
Timing is everything when it comes to dividing and transplanting perennials. For the best results and quickest recovery, it's important to divide plants during their natural resting periods—not when they're actively blooming or during the peak heat of summer. Most perennials respond best when divided in early spring or early fall, depending on their growth habits. Rather than following a strict calendar, the healthiest approach is to observe your plants. If the center of a plant is thinning or forming a “doughnut” shape, blooming has slowed, or the plant appears overcrowded and is encroaching on its neighbors, it’s likely time to divide.
Spring is an excellent time to divide perennials, especially just as new shoots are beginning to emerge and the soil becomes workable. Dividing at this stage gives plants the full season to rebuild strong roots and recover. Early fall is another ideal time—about six to eight weeks before the first frost—when cooler temperatures reduce stress and soil warmth encourages root development before winter dormancy.
On the other hand, it’s best to avoid dividing during mid-summer heat, when plants are most vulnerable to transplant shock. Likewise, dividing while a plant is in full bloom can lead to poor recovery since the plant’s energy is focused on flowering rather than establishing new roots. If dry conditions persist, delay your division unless you can provide consistent moisture through irrigation or hand watering.
By choosing the right time and responding to what your plants are telling you, you’ll encourage stronger roots, more vibrant foliage, and longer-lasting blooms in your perennial garden.
Tools You’ll Need for Dividing Perennials
You don’t need fancy equipment—just a few garden basics will do:
A sturdy spade or garden fork
A sharp knife or pruning shears
A handsaw (for tough roots)
A bucket or wheelbarrow for transport
How to Dig Up a Perennial Safely
Digging up perennials properly is a critical step in the division process. The goal is to remove the entire root ball with as little stress or damage to the plant as possible. Rushing this step—or being too aggressive with your shovel—can lead to torn roots, transplant shock, and slower recovery. A gentle, deliberate approach goes a long way toward ensuring your divided plants thrive in their new location.
Start by assessing the size of the plant and estimating how wide its root system may be. As a general rule, you’ll want to give the plant a generous berth—about 8 to 12 inches from the crown or center of the plant. Using a sharp spade, insert the blade straight down into the soil in a circle around the plant. This creates a boundary and loosens the roots without slicing through the central crown.
Once the perimeter is cut, work your spade or garden fork under the root ball from several angles. Tilt the handle back gently each time to lift the plant a little further with each pass. Avoid yanking the plant upward or levering from just one side, which can damage deeper roots or compact the surrounding soil. Instead, take your time easing the entire plant out of the ground.
If the soil is especially dry or compacted, watering the area thoroughly a day in advance can make digging much easier and less stressful for the plant. For large or deep-rooted perennials like ornamental grasses or mature hostas, you may need to dig wider and deeper to get underneath their more extensive systems. In some cases, inserting two garden forks back-to-back and pulling the handles apart can help loosen stubborn clumps with minimal breakage.
After lifting the plant, gently shake or tap away excess soil to expose the root system. This gives you a better view of where to divide and helps lighten the load if you're transporting the plant to another part of the garden. If roots are tangled or circling tightly, gently tease them apart with your fingers. The goal is to keep as many healthy roots intact as possible—remember, a well-preserved root system sets the stage for fast recovery and strong regrowth.
With a bit of care and the right technique, digging up your perennials becomes the perfect opportunity to refresh your garden while multiplying your favorite plants.
Easy Techniques for Dividing Clumping Perennials
Once you’ve successfully dug up your perennial, the next step is dividing it—and how you go about this depends on the type of plant and your tools on hand. Some plants are soft and forgiving, while others can be surprisingly tough and woody. Luckily, there are several effective techniques that even beginner gardeners can master, and each one ensures your divisions have the best chance to thrive.
For most clump-forming perennials—like daylilies, hostas, rudbeckia, and bee balm—you can simply cut the root mass into smaller sections. Lay the root ball on its side and use a sharp garden spade to slice down through the crown. Start by halving it, then divide those halves again into quarters if the plant is large. This is the most common and straightforward method, especially for medium to large perennials. Each piece should have its own cluster of roots and healthy shoots or buds. Don’t worry if it looks a bit rough—most hardy perennials bounce back quickly once replanted.
If the root system is looser or fibrous, as seen with plants like lamb’s ears, ajuga, primrose, or columbine, you can often divide them gently by hand. Once you’ve removed excess soil and identified the natural separation points in the roots, simply pull the clump apart into sections. These soft-rooted plants are forgiving and respond well to this delicate method, making it ideal for gardeners who prefer a hands-on approach.
For tougher customers—especially those with woody or densely matted roots, like astilbe, lilyturf, or ornamental grasses—you may need a little more muscle. A clean handsaw, pruning saw, or even a serrated knife can be used to carefully cut through the thick root mass. Make sure each division includes some strong root structure and at least one healthy shoot. Using sharp tools helps minimize damage and promotes faster recovery.
Another tried-and-true method for especially dense clumps is the two-fork technique. Insert two garden forks back-to-back into the center of the plant and gently pull the handles apart. This helps pry the clump apart evenly with less damage to the roots. It’s a great way to preserve larger root structures and is surprisingly efficient for splitting stubborn perennials without too much strain on your back or wrists.
When it comes to division size, you have options. In most cases, quartering the root ball provides the best balance—each piece is small enough to replant easily but large enough to reestablish quickly. If you’re working in a large garden or want fast coverage, go for larger sections. For tighter beds or container gardens, smaller divisions are easier to work with and take up less space.
No matter the method, the key to success is making sure each new piece has roots and growth points. Once divided, replant promptly to avoid drying out the roots, and keep the soil consistently moist until the plant settles in.
Dividing Rhizomes and Tubers: A Gentler Approach
Some plants, like iris, canna, and dahlia, grow from rhizomes or tubers. These underground stems or root structures multiply over time, making them perfect for propagation—but they require a bit more finesse.
Once dug up, gently shake or wash off the soil to expose the structure. Use a clean, sharp knife or garden shears to cut pieces that contain at least one healthy growth point or “eye.” Discard any mushy, shriveled, or diseased parts.
Rhizomes (like iris): Plant with the top just above soil level.
Tubers (like dahlia): Plant with the eye just peeking out of the soil surface.
Spacing Leave 10–12 inches between each new division.
Aftercare: Replanting Your Divisions
Always replant your divisions at the same depth they were growing before. For perennials, make sure the crown sits just at or slightly above the soil line to avoid rot. Water deeply after planting to help roots settle in. Keep the soil moist (but not soggy) for the first few weeks while the plant re-establishes.
Add compost or a gentle starter fertilizer if your soil is lacking nutrients. And don’t forget to mulch! It retains moisture and suppresses weeds, giving your new plants a solid start.
Help from Seacoast Gardener
If you’re unsure whether a shrub can be saved—or if it’s time to let it go—Seacoast Gardener is here to help. We offer expert plant health assessments, pruning, and full shrub replacement services throughout southern New Hampshire. Whether you want to salvage a favorite plant or start fresh with a healthier landscape, our team brings deep horticultural knowledge and hands-on care to every yard we maintain.
📞 (603) 770-5072 | 🌐 www.seacoastgardener.com