Perennials - dividing
Has it been several years since you last divided the perennials in your landscape? Are you now ready to divide some if not all of them?
When perennials are first planted, they grow and mature into vigorous plants. It’s the beauty that these plants project that certainly makes planting them a joy, plus once they are in the ground, it can be several years before dividing them becomes important.
Essentially, there are two types of perennials, hardy perennials and tender perennials. Hardy perennials are those that can be planted and basically be left alone at the end of a season. Tender perennials are those that must be dug up at the end of the season, cleaned, and properly stored. Various locations have different requirements as to what is considered “tender” perennials. If you are not in the Treasure Valley area of Idaho, it would be advisable to check what’s considered “tender perennials” in your area.
By dividing perennials, you are providing your landscape with the opportunity to continue producing quality blooms on beautiful, vigorous-growing perennials plants. It also allows you to control plants that may have overgrown an area of the landscape that was designated for them. And by dividing perennials, you are enhancing the overall health of a plant. Dividing plants also gives the gardener an opportunity to introduce some of your existing perennials into new locations around the home without spending more money on new plants.
So you might ask “What is the best time of year to divide perennials”? We recommend dividing them in the fall of the year after they are starting to show dormancy (the leaves are turning or have turned yellow). They can also be divided in the early spring months prior to them growing actively. Not all perennials meet these requirements. Tender perennials for example may require early digging.
Just as a reference, most perennials can be planted any time of year if they are container grown, however in the bulb form they must be planted within a specific time period.
So how can I tell if my perennials need dividing? One way is to look at the center of the plant and see if it is woody or is dying. Most gardeners translocate or divide plants when they begin looking over-crowded. You may also notice that the flowers are somewhat smaller than then they were originally planted. Depending on the perennials planted, you may want to consider looking at them closely after the third or fourth year from the initial planting. Keep in mind this is only a reference and some perennials can go much longer before needing dividing.
When dividing perennials, care should be taken to carefully dig the entire plant from the soil. This allows you to inspect the root system for insects and diseases as well as giving you the opportunity to divide the plant with care. Typically, you don’t want to leave the plant out of the soil for long periods of time. Avoid freezing and thawing and keep out of direct sunlight as best possible. Depending on the perennial you are dividing, you may need a spade or sharp knife to aid you in dividing plants. After dividing, check to be certain that you have removed any dead or unhealthy parts of a plant.