Time to start dahlias from seed (in pots)

Dahlias are beautiful and eye-catching flowers that are a must-have in any garden. There are so many different types and varieties that there’s something for everyone. Can’t wait to grow your dahlias in the garden again? Then you can start forcing dahlias in pots right now. That way, you won’t have to wait until after the last frost to plant them in the ground, which helps prevent frost damage. You can get started right away. Your plants will reach a nice size sooner and bloom earlier, too!

What does "pruning" mean in a pot?

Starting plants in pots means growing them in pots, often indoors or in a greenhouse, before planting them outdoors in the ground. Starting dahlias in pots is a great way to grow and enjoy these beautiful flowers in small spaces such as balconies, patios, or small gardens. You can then easily keep them in a (spacious) pot or planter, or plant them in the ground in your garden once the risk of frost has passed. Starting them in pots offers a number of interesting advantages.

Why should you start dahlias from seed in pots?

• You can start growing dahlias earlier in the season
• You have more control over the growing conditions and soil type for your dahlias
• You can easily bring potted dahlias indoors in case of (night) frost
• It's also easier to protect potted dahlias from things like snails
• Last but not least: your dahlias will bloom even earlier!

When can you start dahlias from seed in pots?

The best time to start dahlias in pots is in the spring. Late March (though that’s still a bit early) or from early to late April is a great time to start the plants.

How do you start dahlias from seed in a pot?

To start dahlias in pots, you’ll need a few things: Of course, your favorite dahlias. These can be dahlias you dug up from your own garden in the fall, or newly purchased dahlias. Use slightly larger pots, preferably with a diameter of at least 27 cm (C10). Ensure good drainage in the pot, for example, by using old terracotta shards, hydro granules, or a layer of (crushed) sand.

Don’t plant the dahlia tubers too deep in the pot. They need enough space to develop a good root ball and continue growing. Use fresh potting soil. Cover the dahlias with potting soil, but always leave a few centimeters free below the rim so you can water them easily and thoroughly. Dahlias need plenty of water and, later on, plenty of fertilizer to grow well.

Place the pots in a bright, warm spot, sheltered from cold winds. Bring the plants indoors if the temperature drops below 5°C, and definitely if there’s a risk of frost.

When the plants are about 10–15 cm tall, you can pinch off the tips. This encourages more compact growth (more side shoots) and results in more flowers later on.

Once the plants are larger (and stronger) and no longer have only young shoots, you can transplant them into the ground. That said, you can also keep them in pots just fine, as long as you’ve chosen spacious ones. Of course, you can also repot them again to give them more room to grow.

Protect dahlias from frost, drought, and snails

Young dahlias are delicate. Dahlias can be damaged by frost, drought, and, of course, snails. Dahlias cannot tolerate frost. Bring them indoors when it gets cold (and be careful of night frost as well). Dahlias also have a low tolerance for drought. So don’t forget to water them during the growing season. You’ll need to keep a close eye on this, especially if they’re in pots.

The young shoots of dahlias are very popular, and snails can cause significant damage to the leaves and flowers of your beloved dahlias. To prevent damage from snails, you can wrap copper tape around the pot. Snails hate copper and won’t crawl over it. You can also use natural remedies, such as coffee grounds, crushed eggshells, or sheep’s wool, and place them around the plants or scatter them. We do not recommend using pesticides or toxic slug pellets for this purpose.