One of our latest plant obsessions is the Dahlia, since growing them from seed and realising just how easy it is to get many years out of these lovely plants.
Perfect for pollinators, as cut flowers and for bold borders, we absolutely love the diversity of plants that can be grown from seed.
I first attempted these many years ago, with a tray of seed under my living room radiator. It was so successful it led me to grow them every year since and as you collect your own seed at the end of each summer, your collecting a huge batch of genetics for the following year!

Favourites can be carefully dug up and the tuberous roots can be divided to create new plants

An essential flower for any gardener who wants to encourage the bees! These flowers are bold and dramatic, attracting so many pollinators to the garden!
Overwintering Dahlia Tubers
We dig up the underground tubers when they finish flowering and bring them into a dry area. If you have space, you can put your tubers into dry sandy soil or sawdust and keep dry and frost free.

You can separate the bigger, mature tubers at this point to create a whole new plant for free!



We grow more Dahlias from seed every year!

When spring arrives and frost is clear we can put them back outside and enjoy their beautiful flowers for another season.
We left some of our dahlias in the polytunnel to see how they would cope and they grew incredibly quickly, and started flowering in April! I could dedicate a whole polytunnel to growing them…. I love them that much!
Dahlias can flower late into autumn, which makes up for the time waited for them to blossom
Sometimes, tubers left in the ground here, survive the Rabbits and less harsher winters and come back stronger than ever!
Tips and Advice
What we have learnt
Rabbits love Dahlia tubers!!! If you do decide to leave your plants in the ground over winter, you may benefit from covering them with something so they cannot be eaten! We are in a rural area and have a massive rabbit problem!
Tall Plants will benefit from support. Plant supports can be bought online or in garden shops and can be placed around the young plant to grow through and not fall over. You can even make one yourself from foraged branches.
Any soil that drains well. We don’t find these to be particularly fussy in terms of soil and have grown them in good and bad areas of the garden. I’ll often see Dahlia tubers unsold at the garden centre in summer, growing into healthy plants inside the plastic packaging with absolutely no soil or watering! Generally they like a rich soil with good drainage so as not to get waterlogged or they can rot. You can always give them an organic plant feed to give them a boost before flowering! Check out our page homemade fertilisers here.
Grow from seed! There are so many different varieties of Dahlia available to grow from seed and we would recommend it to anyone. We start some seed off early in February, indoors under lights and have really good results. They like to be warm and humid and once they pop through, will grow quite quickly. A simple windowsill propagator will do, or you can wait until the frost passes and grow straight outside.
They perform well in pots too. There are many varieties that grow shorter, strong stems perfect for growing in containers as they don’t need plant supports, and the flower heads aren’t so big they keel over. When it comes to collecting tubers, they are also much more accessible as there is no digging required!
Deadheading is beneficial if you want to encourage more blooms to follow. We cut a lot of our blooms for the vase which saves deadheading duties and brightens up the inside at the same time!
Save your own seed for random natural selections the following years! Once they have finished flowering, cut off flower head and pop it in a paper bag or envelope. Let the seed heads cure for a few weeks or until you want to sow them in Spring. Seeds need to stay cool and dark ideally.
Split your tubers to get more plants for free!
If you’d rather read about growing vegetables, see our page ‘The Edible Garden‘ to have a look inside the old greenhouse that is evolving into a permaculture garden.
Follow us on Instagram for more photos of our journey!
More from the blog
- Autumn In the PolytunnelThe nights become chilly and the mornings frosty, the polytunnel has had another hot summer and is finally cooling down. Space is filling up with tender plants in containers and our fruit and veg growing in the raised beds are coming to an end and soon to be replaced with winter crops that are grown … Continue reading Autumn In the Polytunnel
- Polytunnel Progress: Building a Heated Seed BedGoing into 2020 we decided that a heated seed bed inside the polytunnel would be amazing for starting seeds early in the year without having to sacrifice our indoor space! There are many plants that do not require such early start but we will be focusing on those such as Chilli Peppers and Sweet peppers … Continue reading Polytunnel Progress: Building a Heated Seed Bed
- Growing Dahlias from Seed and overwintering tubersOne of our latest plant obsessions is the Dahlia, since growing them from seed and realising just how easy it is to get many years out of these lovely plants. I first attempted these many years ago, with a tray of seed under my living room radiator. It was so successful it led me to … Continue reading Growing Dahlias from Seed and overwintering tubers
- 2019 Growing: Chilli and Sweet Pepper ReviewT’was a hot summer here in the south of England, and our first with the new polytunnel We couldn’t wait to see how our chilli peppers would grow in comparison to previous years being grown in the ground in the old greenhouse. This year we grew chillies in there, as well as in pots, and … Continue reading 2019 Growing: Chilli and Sweet Pepper Review
- First Summer in the Polytunnel2019 is our first summer having the Polytunnel and we’re sharing our successes and failures that came along with it. We have absolutely loved it and couldn’t have hoped for better results when it comes to our growing goals. We did come across some challenges including Managing the Environment. But we also learnt that we’re able … Continue reading First Summer in the Polytunnel
- Growing Summer Hanging BasketsWe’re sharing our experience from start to finish including which plants we used, compost, fertiliser and a review of the whole process. Including failures!