​How to Deadhead Dahlias

Posted by Amber Williams on 7th Jun 2024

​How to Deadhead Dahlias

Your dahlias are in their prime right now, giving your garden a glorious summer hue. But what should you do with flowers that are past their best? And how should you go about pruning back flowers that have died back?

Deadheading dahlias is an important practice to help your blooms stay healthy and grow new buds. If you’re new to gardening or just dahlias, and you’re unsure of where or how to deadhead your dahlias, then our guide will show you the ropes!

What does deadheading mean?

A gardener holding secateurs and deadheading a dead rose

Image: A gardener deadheading a spent rose

Deadheading is the process of cutting off ’spent’ flower heads. Spent meaning past their best, drooping, shrivelled, or for a lack of a better word, dead. Deadheading means removing these spent flowers, allowing the plant to refocus its energy into growing new buds. This will keep your displays looking floriferous throughout the season, or for as long as possible.

Deadheading is an easy task, and you don’t need to be Alan Titchmarsh to pull it off (no pun intended).

How to deadhead dahlias throughout the flowering season

Okay, so there is a bit of an art to deadheading dahlias - or any flower for that matter! Here’s a quick guide to help you out.

- Wait until the flowers show signs of wilting or are completely wilted.
- If there are multiple heads per stem, cut the wilted flower back to the bud joint
- For single stems, cut them back to the next set of leaves
- Do this every few weeks to keep your flowers thriving

Deadheading should be done regularly to help the plant grow new buds. If you leave them on, the plant will be sending all its energy into a flower that cannot be rejuvenated. Cutting the spent flower heads will then allow the plant to focus all that energy on creating new buds, allowing the cycle to continue throughout the season.

What to do with dahlias once they’ve died back

Deadheading can be done while the plant is still alive and thriving. But what do you do once the whole plant has died back? This is a different can of worms.

Between the time they finish flowering and storing your dahlia tubers, there’s still work to be done. When you’re sure the plant has died back and will not flower again, you can begin to cut off old flowering stems from the base, about 5cm away from the ground. Feel free to throw these stems into the compost or garden bin.

Use Our FREE Dahlia Growing Guide

Are you new to growing dahlias? Or in need of a refresher course? Our Dahlia Growing Guide is a handy piece of advice to keep on hand, as it’s full of our top tips for growing and caring for your Dahlia blooms. From the moment you bring them home from the garden centre to after-care advice, it has everything you need to know to keep them in perfect condition for the following year (and save you money on new plants in the long run!).

Want to learn more about dahlias? Our blog is full of dahlia advice and articles, like our ‘What to Plant with Dahlias’ guide, and our ‘Everything You Need to Know About Dahlias’ long-read.