Plant dahlia tubers in well-drained soil after the last frost. Place tubers 4-6 inches deep, spaced 12-18 inches apart, with eyes facing up. Water thoroughly. Let’s talk about how to grow dahlias from tubers!
How to Grow Dahlias from Tubers
There are three methods for how to grow dahlias from tubers;
- Tubers,
- Cuttings, or
- Seeds.
Tubers are the roots of mature plants and appear as clusters of brown, carrot-like roots connected by dried stems from previous years. You can purchase tubers from garden centers by mail orders in spring, or overwinter your tubers at home.
When to Plant Dahlia Tubers
Starting dahlia tubers indoors early is an effective way to kick-start their growth earlier. Plant dahlia tubers in large pots filled with peat-free multipurpose potting compost in March or April and then store them on windowsills or frost-free greenhouses until late May when it’s safe to move them outdoors.
Starting Dahlias off in pots will also help them grow faster, so that they may start flowering earlier. Before planting, soak their tubers for one hour in warm water to fully rehydrate them before placing them into the soil.
Growing Dahlias in Pots
Dahlias can be grown all year long in containers for an attractive splash of color on patios and balconies. Small to medium-sized dahlia varieties such as Mignon and Ruff Dahlias as well as water Lilly Ball & Pompom Dahlias work well – to avoid tall cacti Dahlias which require constant staking, opt for dahlia varieties that don’t usually need support.
Dahlias should be placed in a warm, sunny location away from strong winds and watered regularly; once every week fed with phosphate-rich liquid fertilizer.
Select free-draining, peat-free compost and place the tubers so their buds on the tuber shaft are only lightly covered by soil. Water well before pinching offshoots at approximately 10cm long to encourage bushy growth.
Winter-hardy potted dahlias should be moved to a frost-free spot such as an unheated greenhouse for storage. When spring arrives, remove as much compost from around and above tubers as you can and replace it with fresh compost – this will provide them with essential nutrients needed to produce stunning displays!
Steps to Grow Dahlias From Tubers
Here are the steps on how to grow Dahlias from Tubers:
Things You Will Need:
- Dahlia tubers
- Large pots
- Peat-free multi-purpose compost
- Plant labels
- Pen
Step 1:
Planting Dahlia Tubers In Pots
When planting dahlia tubers in pots, ensure the joint where the roots meet the stem is facing upward. Label your pots and place them in a greenhouse or sunny windowsill to grow on. Be sure to water regularly.
Step 2:
Pinch Out The Growing Tip
For best results, pinch off the tip of the main shoot, down to its pair of leaves at its base. Also, remove most shoots growing from the tuber except five shoots that form bushy plants with strong growth and more flowers. This process should produce bushier plants with bushier growth and increased flower production.
Step 3:
Harden Off Dahlia Plants
Once all risk of frost has passed, harden off your dahlias by leaving them outside during the day and bringing them in at night for one week before planting out into their final growing positions.