To divide or not divide that is the perennial question and here are some answers to help you along the way.
Why should you divide?
Dividing perennials will promote healthier plants and for plants that are producing fewer or weaker blooms dividing is just the slice they need to rejevinate their life. Dividing is also a technique used to keep invasive perennials under control and dividing is a great way to create more plants and help fill ever expanding gardens.
When should you divide??
The easy rule to remember is to divide spring and summer blooming perennials in the fall and fall blooming perennials in the spring. Dividing in fall should happen at least 4 to 6 weeks before the ground freezes to allow healthy root establishment. In the spring the earlier you can divide the better, the goal is to divide and allow the roots enough time to settle in before hot weather arrives. Spring divided perennials will suffer from minimal shock meaning they often bloom a little later than usual.
Dividing should never happen on hot sunny days. The ideal condition is on a cloudy day with several days of cloudy rainy weather in the forecast. In fact one of the best times to divide is during a day of light rain.
Perennials should be divided every three to five years, the expection are bleeding hearts and peonies. These beauties can go years with out division that is unless you want more of them. When dividing peonies be careful not to plant the eyes of the peonies too deep or they just will not bloom.
Rules of the road:
Water perennials deeply a day or two before dividing. Prepare the area that you plan on moving divisions to. Use a sharp spade or folk to dig down and lift the parent plant. Use a spade or sharp garden knife to remove a natural division from the parent plant. Natural division are easily found and appear as separation within the plant itself. Never allow division to dry out and trim all broken or damaged roots before replanting.
Replant divisions immediately into the garden or containers, placing them into the soil at approximately the same depth they originated. Firm soil helping to remove air pockets and water deeply.
Finally for those perennials divided in fall I suggest mulching to provide some insulation. This will further help with root establishment and will prevent heaving created from the frost and thaw cycle of winter weather.
Happy Dividing!!
Frankie
Frankie Fab Five Non-Invasive Perennials:
Salvia ‘May Night’
Selected as Perennial plant of the year by the PPA this long blue flowering beauty is hardy to Zones 4-8. A late-spring blooming perennial with rigid spikes of dark blue-black flowers appear over aromatic blue-gray leaves in May and June. Plant in full to part sun.
Miscanthus sinensis ‘Little Kitten’
New in 2004 is a narrow, silver-green, non-invasive grass that grows 45 centimetres tall, with 75-centimetre, cream-coloured plumes and beige seedheads in fall. Tolerates heat, drought and cold. Plant in full sun to part shade hady to Zone 5.
