Updated: Oct 31, 2019
When it’s time to divide your spring- and summer-flowering perennials, consider adding another layer of color and texture with spring-flowering bulbs. First, let’s talk about perennials and why and how you divide them.
Perennials, plants that return year after year, provide seasonal flower and foliage color. Some are early spring risers, producing a spectacular floral display at the end of winter, like hellebores. Others make a statement later on. Perennials such as Russian sage and New England Aster add height and texture with foliage during the summer and deliver a blast of flower power in late summer or early fall.
Many perennial plants, like hostas, turn yellow and die completely to the ground in the fall. It’s as if they were never there. Other perennials, such as liriope, and those that grow in tropical or mild winter locations, are evergreen. At some point, all perennials will need to be divided.
Divide and Multiply
Eventually, you’ll need to divide perennials to remedy or avoid overcrowding and to increase flowering. Most perennials require dividing after several years in the same place. You’ll know when the time is right because a) the plant looks tired and is producing fewer flowers and/or b) the plant has outgrown its location.
Another reason to divide is simple multiplication. Want more of your favorite perennial to install in another area of your garden or to share? Dividing is a free method of propagation. While a trip to the nursery is always fun, you can divvy up existing plants in your own backyard without spending any cash.
Dividing plants is simple and uniquely satisfying — for some gardeners it’s right up there with growing plants from seeds. Before you do any dividing, decide where you want to plant the new divisions. Dig those holes first. Depending on what bulbs you’re going to plant, you’ll probably need to adjust the hole depth. More on that later.
Divide spring-flowering perennials in the fall after their leaves have yellowed. Use your digging tool of choice — a garden fork, shovel, or spade — to dig out the clump of perennials that you want to divide. Make sure you get underneath the roots. Ease the plant out of the ground. Brush off enough soil so you can see where natural divisions appear. You should be able to see older growth toward the center and newer growth at the edges. Use your hands or two hand forks to separate clumps. Set clumps aside in the shade so the roots don’t dry out. You’ll need to replant new divisions as soon as possible.
Fall is the time to plant spring-flowering bulbs so it’s the perfect intersection of timing for division and planting. Choose spring-flowering bulbs with an eye on timing for the most bang for your efforts. For example, tulips and daffodils are usually labeled as early-, mid-, or late-blooming. If you plant a mixture of those types, you’ll have flowers for two or even three months rather than just a couple of weeks. Also consider installing smaller bulbs like dwarf iris, snowdrops, crocus, or grape hyacinth.
Planting and Replanting
Following the instructions for planting depth on the package, plant bulbs in the holes that you dug for the new divisions. Place your new perennial division on top of the bulbs, backfill with soil, and water in. It’s a good idea to mark your new plantings, either with a physical marker or with a photo that you can keep in your garden journal. But, that’s a whole other project…
Blog by Jaqueline Murphy, Plant Expert, BloomCatch