How to Divide Perennials in Fall | Preparing for a Plant Swap, by Gardens By Monika on YouTube. 29 min 6 s.
- Video length
- 29 min 6 s
- Time to do it
- 45 minutes
- Difficulty
- Easy
- Steps
- 9
What you need
Steps
Pick the window. Divide from late September through early October, when the soil is still warm and the air is cool. Plants settle in before winter instead of stressing in summer heat.
Choose plants that need it. Look for clumps with dead centers, sparse flowering or roots pushing out of the soil. These are the ones that benefit most from splitting.
Water the plant deeply the day before you dig. Damp soil holds together better and makes the root ball easier to lift without tearing.
Dig around the drip line with a fork and lift the whole clump. Work the fork under the root ball and lever it up gently rather than pulling the stems.
Split the clump. Push two forks back to back through the middle and lever them apart, or cut clean sections with a sharp knife. Keep pieces with roots and healthy shoots.
Replant the best division in the original spot at the same depth it grew before. Firm the soil around it and water well to settle out air pockets.
Pot the spare divisions for the swap. Use fresh potting mix, water them in and label each pot with the plant name and color.
Keep swap plants in a sheltered, bright spot and check moisture every few days. Bring them to the swap once they look settled, usually in a week or two.
Finish the fall bed work. Cut back spent foliage, clear debris and top the beds with compost before the cold sets in.
Tips and common mistakes
Never divide a plant that is already struggling with pests or disease, since the stress can kill it.
Do not bury the crown deeper than it sat before, or the plant may rot over winter.
Divide and replant on a cool, cloudy day so roots are not exposed to sun and wind.
Wear gloves when using a hori hori knife, and cut away from your body.
Questions
Which perennials should I not divide in fall?
Spring and early-summer bloomers that flower on old wood, like some bearded iris and peonies, often do better divided in late summer or early spring. Check your plant before digging.
How big should divisions be for a plant swap?
A piece with three to five healthy shoots and a good root mass is plenty. Smaller pieces survive but take longer to establish.
Do I need to water fall divisions through winter?
Water them well at planting and again during dry spells until the ground freezes. Newly divided plants have shallow roots and dry out faster.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
