Your Dahlias Can Survive Winter in the Pot. Here's When They Can't., by Pollinator Yard Guide on YouTube. 21 min 20 s.
- Video length
- 21 min 20 s
- Time to do it
- 1 hour plus winter checks
- Difficulty
- Medium
- Steps
- 9
What you need
Steps
Wait until the first hard frost blackens the leaves, then cut the stems back to about 10 cm above the soil. This stops the plant pushing energy into dying top growth.
Decide your method. In mild areas you can leave tubers in the ground under a thick mulch. In cold, wet areas lift them or move pots under cover.
For pots, stop watering once the foliage dies back. Move the pots to a frost-free shed or garage and keep the compost almost dry all winter.
To lift tubers, fork around the clump well away from the stems, then ease the whole root ball out without snapping the necks.
Shake off loose soil but do not wash the tubers. Let them dry for a day or two in a cool, airy spot out of direct sun.
Store tubers in a box with dry compost, sand or newspaper, stem ends up. Keep them at about 5 to 10 C and check them monthly for rot.
Cut away any soft, brown or mouldy sections with a clean knife as soon as you spot them. Healthy tubers stay firm and plump.
In early spring, divide large clumps so each piece has at least one eye and a piece of stem. Label each one.
Plant out after the last frost, about 30 cm apart, with the crown just below the soil surface. Water in and stake tall varieties.
Tips and common mistakes
Wet soil is the main killer of stored tubers, so keep compost and storage material dry.
Never store tubers in a warm room, they will shrivel or sprout too early.
Check stored tubers every few weeks and remove any that feel soft.
Leave a short piece of stem on each tuber so you can see the eyes when dividing.
Questions
Can I leave dahlias in pots all winter?
Yes, if the pots stay frost-free and the compost stays almost dry. In cold, wet areas move them into a shed or garage.
Why did my stored tubers rot?
Usually too much moisture or poor airflow. Dry them well before storing and use dry material in the box.
When do I cut dahlias back for winter?
After the first hard frost has blackened the leaves. Cutting earlier can push new growth that winter kills.
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.
