With their lacy petals and vast array of shapes and sizes, dahlias have stepped into the spotlight as the flower of the moment. Lynda Hallinan shares four key tips for growing them at home.
1. Don’t despair at the start
Like daffodil bulbs and gladioli corms, dormant dahlia tubers aren’t much to look at when you buy them. Brown-skinned and slightly wrinkly, they remind me of wizened kūmara that have lingered for too long in my kitchen cupboards, but don’t despair as the size of the tuber bears no relation to the beauty within.
2. Plant tubers the right way up
When planting, bury dahlia tubers with their narrow necks (the growth eye) facing up. If you’re not sure which way is up, lay the tubers on their sides. Plant 10-15cm deep in a sheltered, sunny spot in fertile, free-draining soil.
3. Consider a winter planting plan
Dahlias are frost-tender. In cooler climates, lift the tubers when the foliage yellows off in late autumn, then store them indoors in trays of sawdust or pea straw over winter. Replant after the risk of frosts has passed in early spring.
4. Enjoy a propagation station
Dahlias are generous self-propagators. Erin Benzakein describes them as akin to a sourdough starter: “Once you have it and as long as you take care of it, you’ll have a steady supply to share with others.” Simply uproot established clumps, shake off the dirt and gently prise apart their roots into separate tubers to gift to friends.