As gardeners, we often ponder the intricacies of plant care, especially when it comes to perennials. One common question is, "Why do some perennials need to be divided while others don't?" As with many gardening practices, there's both art and science involved. Dive in with us to learn more about perennial division.
When you divide perennials you’ll provide them with the best growing conditions, and you know what that means for you? More flowers!
Vigor and Health: Over time, certain perennials can become overcrowded, leading to a decrease in bloom quality and plant health. Dividing them rejuvenates the plant, giving them more space and better access to nutrients.
Propagation: It's a great way to multiply the number of plants you have without buying more. If you have a favorite perennial, dividing can help spread its beauty to other parts of your garden.
Disease Control: Overcrowded plants are more susceptible to diseases. By dividing them, you can reduce the risk of disease spread.
Not all perennials grow the same way and so do not require the same care. Here's a quick breakdown:
Clump-forming perennials, such as daylilies or hostas, grow outward from the center. Over time, the middle may die out, leaving an unattractive, donut-shaped hole. These benefit most from division.
Spreading perennials, like mint or bee balm, send out runners or rhizomes. These can become overgrown if not kept in check. Division helps control their spread.
Taproot perennials, like columbines or oriental poppies, grow from a central, thick root. These typically don't need division for the health of the plant, and doing so can be challenging.
Just like soil nutrients and pest control, you’ll have the most success with gardening when you provide your plants with ideal growing conditions. For clump-forming perennials that means dividing them. The frequency of division varies. Check the information below to know how often your garden favorites need division, whether for healthy blooms, to control spread, or if they don’t require division at all.
While many perennials benefit from periodic division, it's essential to understand the specific needs and growth patterns of the plants in your garden. A well-maintained garden is not only more aesthetically pleasing but also promotes healthier plant life.
To maximize the number of blooms, the size of blooms, and to optimize your garden's health, divide perennials that benefit from the practice because when done correctly and at the right time, can yield abundant rewards.
| Perennial | Divide Every: | Special Requirements: |
|---|---|---|
| Hostas | 3-5 years | Divide when the plant is dormant. Water well after replanting. |
| Daylilies (Hemerocallis) | 3-5 years | Divide when the flowers have finished blooming. Replant immediately and water thoroughly. |
| Iris | 3-4 years | Divide after flowering. Cut leaves back to about six inches and replant rhizomes just below the soil surface. |
| Peonies | 10-15 years | Divide in early fall. Plant with the eyes (buds) no more than 2 inches below the soil surface. |
| Sedum (Stonecrop) | 3-4 years | Divide in early fall. Replant in well-drained soil. |
| Asters | 2-3 years | Divide in early fall. Plant in a sunny location with well-drained soil. |
| Chrysanthemums | 2-3 years | Divide in early fall. Plant in full sun and water well. |
| Coneflowers (Echinacea) | 3-4 years | Divide in early fall. Plant in a sunny location with well-drained soil. |
| Ornamental Grasses | 3-5 years | Divide in early fall. Replant in a location with full sun to partial shade. |
| Yarrow (Achillea) | 2-3 years | Divide in early fall. Plant in full sun with well-drained soil. |
| Shasta Daisy | 2-3 years | Divide in early fall. Plant in full sun and water well. |
| Coral Bells (Heuchera) | 3-5 years | Divide in early fall. Plant in partial shade with well-drained soil. |
NOTE: Specific requirements for dividing and planting may vary depending on your local climate and soil conditions. Consult your County Extension Office to understand the specific needs of plants in your area.
