How to Start Off Dahlias with Pots & Trowels

Dahlias are a popular flowering plant, and it’s easy to see why. The bright colours add life and style to your garden. They come in different shapes and sizes, they can be grown in containers or in beds, or they can be used as a great filler for borders, taking up space between shrubs and perennials. Dahlias will flower from mid to late summer all the way through to autumn, when the frost will cut them back.

You’ll find many varieties of dahlias, from tiny pompom type dahlias to huge blooms, such as Café au lait tubers from our friends at Mr Fothergill’s, and everything in between. This attractive and diverse plant is a perfect all-rounder.

Dahlias all grow from a root tuber, and this time of year is a great time to start your dahlias off. You can find them in garden centres pre-packed and ready to go. There are different types of tubers, but dahlias are grown from swollen underground tubers that act as a food store, keeping the plant ticking over whilst dormant.

There are different ways you can grow your dahlias. They can be planted directly into the soil or you can start them off in pots. In a recent Pots & Trowels video, Martin Fish shared some expert advice to help you pot your dahlias and give them the best chance of a long flowering season. Watch his video below or keep reading this for top tips and advice to help you plant dahlia tubers.

The Darlac Mini Snips are perfect for tidying up dahlia tubers

What Equipment Do I Need to Pot Dahlias?

Here’s a list of the items you’ll need for potting dahlias:

  • Dahlia Tubers
  • Compost
  • Pots
  • Labels
  • Snips – try the Darlac Mini Snips. These little snippers have rust-resistant stainless-steel blades and a single hand locking mechanism – simply squeeze the handles and push the catch forward. A perfect friend to help with tidying up your tubers before planting.

How to Prepare Dahlias for Potting

Inspect your dahlia tubers for any signs of damage


Open the bag, bring out the tuber and inspect it. A root tuber is very different from a stem tuber. With a root tuber, you’ll find it’s made up of different elements. There’s the fleshy swollen root part, and then you’ll see a stem element from the plant that grew last year.

The stem must be attached to the tuber for it to grow. The root on its own is no good. The dormant buds that will grow to make the new shoots are all around the collar where the roots and stem meet. Without the stem, it won’t grow. For example, if you find broken root elements in your packaging, you’ll need to get rid of them. Do not pot them as they are, unfortunately, damaged roots and therefore can’t be used.

Be sure to inspect your tuber and look for damaged parts. Damage can happen when tubers are lifted from the field. If you spot damaged parts, you’ll need to trim them off. This includes broken or loose roots and very fine roots. Try snipping these off with the Darlac Mini Snips. They are small enough to help you with delicate trimming, but not too small that they’re hard to handle. Your dahlia is then ready to pot.

Inspect your dahlia tubers for any signs of damage

How to Pot Dahlias

‘Potting’ your dahlia means you start the growth process in a pot which is stored in a conservatory, cold frame or cold greenhouse. The key here is to keep the plant frost free so it will start to grow. This will mean you’ll have a growing plant that you can then transfer out into the garden when the risk of frost has gone. Timing wise, this means you should be potting your dahlias around mid-March to get them into growth. However, if you would like to propagate from your tuber, then you’ll need to pot them a little earlier in the season.

You’ll need multi-purpose compost and a pot. The size of pot will depend on the size of your tuber. You’ll want to make sure there is enough room in your pot, but you don’t need to go too big.

Hold your tuber in the pot by holding the stork/stem, then trickle compost around the tuber, making sure the swollen roots are in contact with moist compost. Give the pot a shake and allow the compost to filter down between the roots, so there are no big air gaps. If you’re planting your tuber in the garden, you’ll want to ensure the stem is soil level, and everything else is buried. Yet, in the pot, you can leave the stem slightly proud, especially if you are taking cuttings for propagation.

Don’t forget to add a label, as each tuber will look similar and you’ll want to know which plant is which! Then, add a drop of water to moisten the compost. After two or three weeks, you’ll see little buds developing and you’ll know growth is in full swing.

Aim to pot your dahlias around mid-March to get them into growth

How to Plant Dahlias in the Garden

If your tubers are going to be planted directly into the garden, then they wouldn’t be put out at this time of year – they should be planted no earlier than mid-April. The soil in April will be warm enough and they should start to grow. This process has to been timed so the tender shoots can push through soil, meaning the risk of frost should have gone. Frost will cut them back and cause you problems. Do note that they won’t grow until May time in the garden, so it’s best to get the timing for planting right.

Where to Buy Darlac Tools

Make life a little easier for yourself by using the right garden tool for the job. You can find our Darlac products in store from your local garden centre. Find your local Darlac stockist here.

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