How to Grow Dahlias

Give your dahlias the best chance to grow healthily by preparing your soil for their arrival. Dahlias thrive in warm, well-draining soils in view of the sun. If you really want to treat them to a luxurious stay in your garden, feel free to dig in some feeds and fertilisers.

When it comes to growing dahlias from scratch, you’ve got two options: dahlia seeds and dahlia tubers. But if you’re wondering how to sow dahlia seeds, you’re going to want to stick around for this information!

How to sow dahlia seeds

Dahlia seeds should be sown indoors between the months of February and April in trays and containers. Whilst they may be inside, they still appreciate the sunlight! We recommend keeping your containers or trays on a well-lit windowsill with plenty of sunlight. 

When sowing, ensure that seeds are around 0.5cm deep and 2.5cm apart. When they’re large enough to handle, it’s time to transplant your dahlia plants into a larger pot so as not to restrict the growth of their roots.

Taking good care of your dahlias is important for maintaining their health and beauty! So don’t forget about them once they’re in the soil; there’s still plenty more gardening to be done.

Feeding

Dahlias love a good meal - it takes a lot of energy to look that good, after all! We recommend using a feed once a week during the earlier stages of growth. By the end of June, your flowers should be ready for a weekly meal of fertiliser until around the beginning of autumn.

Deadheading

The gardening world is a brutal one, and sacrifices must be made for the greater good! If you notice any of your dahlias fading or dying, it’s best to deadhead them. This allows your plant to focus its energy elsewhere and produce other blooms. 

Cutting

When you’ve worked this hard to plant and care for your dahlias, of course, you’re allowed to show them off! One of the most rewarding parts of growing flowers is taking cuttings and displaying them around the home. So let’s find out how to take dahlia cuttings, shall we? 

Select your flowers and cut their stems at the node. Your next step is to remove any leaves that would sit below the water level in your vase. Pick out your best vase and showcase your colourful blooms in your interior. If you’re feeling especially generous, you could even gift a bouquet to your loved ones!

Stalking

As your dahlias grow, they may need a little support - especially if you’re living in a windier area near the coast. Stalking is a great way to support your plants and help them stand tall. We recommend using twine and bamboo sticks. 

Pests and Diseases

Pests like slugs, aphids and caterpillars tend to be attracted to dahlias - who wouldn’t be? So you’ll need to take the necessary precautions to protect your blooms. You could choose to make a barrier, or use an insecticide or a repellent to make sure the bugs know that your flower beds are no all-you-can-eat buffet. 

Dahlias can also suffer from diseases like powdery mildew. This can be avoided by keeping your soil moist and your flowers watered. It also helps to make sure they’re well-ventilated to reduce the possible spread of disease.