Save Your Money This Spring! Divide These 9 Perennials in March to Get More Plants for Free

Early spring is a good time to get started on garden chores such as dividing fall-blooming perennials. Most perennial plants benefit from division every three to five years. But a few of the more zealous growers, such as aster and bee balm, can be divided more often. Other plants, such as hosta or siberian iris, can go up to a decade without needing to be divided.

How can you tell when it’s time to divide perennials? Plants will often lose vigor, die out in the center, produce less flowers, or blooms will appear smaller. Dividing plants gives them room to breathe and absorb more nutrients. Flowering improves and the whole plant rejuvenates. If your plants are fast growers, it is especially important to keep up with division.

March is the perfect time to start dividing late-blooming perennials. I’ll share which species will benefit most from division this month – and which ones you should leave alone. Not only will dividing the right perennials give them a boost, but it will also help you expand your garden for free! You can even share your propagations with friends and neighbors to help them grow their garden without spending a cent.

Plants You Shouldn’t Divide in March

Save your spring and summer-blooming perennials for when you’re dividing plants in the fall. Divide them four to six weeks before the first frost so they have time to get established. If spring or fall don’t work for you, just remember not to divide perennials when they are flowering.

Other plants have long taproots or root systems that are not amenable to division. These include plants like butterfly weed, columbine, Russian sage, baptisia, euphorbia, baby’s breath, or peony.

Hellebores do not like to be moved either and are not easily divided. But you may find small seedlings nearby that you can transplant. Instead of dividing the above plants to grow more of them for free, use another propagation method such as seeds or cuttings.

Perennials that form small, woody shrubs such as santolina, candytuft, lavender, and rosemary don’t divide well either. If their lower branches touch the soil and root, you can cut off and replant those rooted branches to grow new plants for free.

Tips for Dividing Plants in March

Follow these tips before dividing plants in spring or anytime of year:

• Wait for a cloudy day to divide and replant to prevent the roots from drying out.
• Water the plants you intend to divide a couple days ahead, if the area is dry.
• Be sure to prepare the soil ahead of time in the new location or have containers ready.
• Assemble the proper dividing tools: sharp shovel, spading fork, hand saw, garden knives.

Essential Tools for Dividing Plants

Best Perennials to Divide in March

Now that you understand the basics of dividing plants as well as which perennials to leave alone in spring, I’ll share the best perennials to divide in March to get more plants for free.

1. Asters

Aster (Symphyotrichum spp.) is one of the go-to blooming perennial plants, along with garden mums, to add vibrant color to the fall garden. Their root systems may be spreading or rhizomatous.

Dig up the whole plant as new foliage emerges in spring. Shake off the soil and divide asters into two or three sections, each with several roots and foliage. Discard the center piece as it tends to die out. Asters may need to be divided every two to three years because they can spread aggressively.

2. Bee Balm

Bee balm (Monarda spp.) is a popular pollinator plant and its many cultivars are easily found in garden centers. Its spreading root system can be divided every two to three years to keep bee balm plants under control. These native plants can be a bit aggressive and need plenty of room to grow.

Dig up the whole plant in early spring. You can throw out the center part that is dead and replant the other sections or share them with friends. Be sure each section has plenty of roots and foliage to sustain it. Replant at the same depth as the original clump and water well.

3. Catmint

Catmint (Nepeta spp.) is an aromatic herb that attracts pollinators. It doesn’t spread as quickly as typical mint species, but you can divide it every two to three years if needed.

Dig up the clump in early spring and pull it apart into several sections and replant. Make sure there are sufficient roots and foliage in each division. If it doesn’t need dividing, prune catmint back in spring to make way for fresh foliage. In midsummer, shear it again by half to encourage more blooms.

5. Daylilies

Daylilies (Hemerocallis spp.) are a staple in many gardens and require little maintenance. Daylilies have clumping root systems that can be divided in early spring or late summer to fall every three to five years. Diminishing flowers is a sure sign they need division.

Dig up the whole clump and carefully pull it apart, shaking off the soil. You may need a knife to divide daylilies if the roots are very dense. Keep two or three leaf fans in each section along with healthy roots. Plant them with the crowns situated about 1 inch (2.5 cm) below the soil line. Water well.

5. Chrysanthemums

Garden mums (Chrysanthemum spp.), like asters, are one of the favorite flowers of fall. Their bright colors come in many forms such as single, double, pompon, quill, spider, and more. If your mums were planted in fall and made it through the winter, you should see new growth in early spring.

Mums planted during spring have all year to establish and typically perform better than fall-planted mums. Divide them every two to three years to keep the clump growing and blooming vigorously in the fall.

When you see new growth in spring, dig up the clump and shake off excess soil. Cut or pull apart two or three sections and replant, making sure there are roots and foliage in each new section when you split your mums. Water well.

6. Yarrow

Yarrow (Achillea spp.) is a staple in pollinator gardens. Its ferny foliage and flat-topped flowers give it a delicate appearance. Divide yarrow by half every one to three years as these plants can spread rapidly. Divide annually if they get out of bounds.

Dig up the clump and shake off loose dirt. Cut or pry apart divisions, keeping several roots and leaves in each section. Replant immediately and water well.

7. Coneflowers

Purple coneflower (Echinacea spp.) is a knockout native flower with many beautiful cultivars and colors. Its spreading root system expands the clump, plus it reseeds readily. Divide purple coneflower every three to five years in spring or fall to rejuvenate the clumps.

Its roots can grow very dense so you may need a sharp shovel to dig and divide coneflowers. Knock off some of the soil so you can see the roots. Replant at the same level in prepared soil and water well.

8. Garden Phlox

Tall phlox (Phlox paniculata) or garden phlox attracts butterflies and hummingbirds with clusters of colorful flowers. The old-fashioned flower variety spreads faster than new cultivars. They respond to division in early spring or late summer every two to four years.

Dig up the clump and shake off the loose soil. Cut the clump into sections and discard the withering center. After dividing phlox, replant it at the same depth as the original clump and water well.

9. Tickseed

Tickseed (Coreopsis spp.) is a great garden performer and pollinator plant. It increases quickly so you can divide it every two to three years in spring or fall to keep this perennial in check.

Dig up the clump and remove loose soil. Pry apart or cut sections so that several roots and leaves remain in each division. Replant at the same depth as the original clump and water well.