The cooler months of fall are the best time of year to divide overgrown perennials in your garden beds and borders.
Gardeners divide perennials for a number of reasons. They may simply be too big for their current space in the garden. Overgrown perennials also show reduced bloom and flower scape formation. Gardeners also may simply want to propagate new plants from a large, overgrown clump.
Many perennials are actually quite simple to divide with the proper tools and at the proper time of year.
Some perennials, such as daylilies, hostas and others can be divided just about any time of year. These will come back just fine the following season.
Fall is the best time for dividing the widest variety of perennials in your garden, as the soil is usually easier to work, the plants themselves are beginning to go dormant, and there is still plenty of time left in the growing season for the new transplants to establish before the first freeze.
Fall is also the easiest time to divide perennials as you can simply cut back this year's foliage, making separation of individual plants much easier.
Dividing perennial clumps
To divide large, clump forming perennials such as hostas and daylilies, the easiest way to split into smaller divisions is to simply dig up the whole clump with a garden fork.
Rinse the root ball thoroughly with water or soak overnight. Once all of the soil is removed, separate individual plants that include at least one growth point and a nice root system by hand, or, if necessary, with a sharp knife.
Another easy division method is to remove the foliage then use a sharp spade to cut the plant into wedges or slices like a pie or pizza. Each individual wedge can then be replanted in the garden.
These can be replanted where desired immediately.
Bearded iris are also popular plants for fall dividing. Lift the clump and separate the intertwined rhizomes with a sharp knife, or by simply breaking them apart with your hands. Again, each new transplant should include a healthy section of rhizome and at least one fan of leaves.
Some perennials are a little more difficult when dividing because of their growth habit. This includes plants such as coral bells, Oriental poppies, wild columbine and others that form rosettes.
In many cases, these rosettes may barely contact the soil.
To separate, cut off rosettes that form around the center of the main plant. This may require some work as tendrils and stems may be intertwined.
Dividing herbaceous peonies
Peonies are also divided during the fall season. Because established peony clumps can have extremely large root systems, it may require two people to complete the job.
Dig the clump, which may have grown quite deeply, then use a sharp tool to cut individual sections of the root which contain at least one growth point for transplanting.
Dividing perennials is a great way to increase plant bloom and propagate new plants to share or fill new space in the garden, as well as give plants a renewed vigor.