Dahlias - my learnings and thoughts

by Claire Austin May 16, 2023

I really love dahlias, but I’m new to them. I've been doing some research on how and when to dig them up and propagate them. I thought I’d share my thoughts and plans.

Last year, I had a range of dahlias growing in the veggie patch. They did well, but they didn’t like the western sun. I’m going to move them and the best thing about dahlias, apart from the flowers, is they can be easily propagated. I really like how amazing they look en masse and would like to keep a selection growing in a dedicated spot. Im yet to work out where yet. I’ve got a little while to work that out and then prepare garden beds. I will propagate some others and scatter them and use as fillers on the garden beds with salvia, sedum, agastache and roses.

The veggie patch soil is fairly well draining, so I won’t dig up and divide until Spring.

In the areas that are heavier clay, I’ll dig the dahlias up in winter and divide them and store them until they start getting shoots. Then I will plant in their new spots.

Key learnings

What dahlias like:

Morning sun and afternoon shade
Lots of water (this is why I had them in the veggie patch)
To be watered at ground level. The sprinkler spoils their developing blooms. This year I’m going to set them up with brown irrigation line
Well drained soil.
Liquid fertilizer - I use seasol

Managing the ones in Heavy soil

Once they die off, dig up with a pitch fork and divide. I’ll this in winter. They might rot in the heavy, soggy soil.
Store away from mice etc.
Label the ones I know the names of!

Managing the ones in well draining soil