Our dahlias are grown with care here at Ophelia Flower Farm and we want you to have the best possible success with them.
For everything you need to know—from planting to storage—please read our Dahlia Tuber Care Guide below.
When to Plant
Plant dahlia tubers in spring once the risk of frost has passed and soil has warmed. Here at Ophelia Flower Farm in the Waikato, NZ, we aim to plant around Labour Weekend in October as the risk of frost has mostly passed.
Choosing a Location
- Full sun (at least 6 hours daily)
- Well-draining soil
- Protected from strong winds
Planting Instructions
- Dig a hole 10–15cm deep
- Lay the tuber horizontally with the eye/growth facing up
- Cover lightly with soil
- Do not water until shoots appear
Watering
Once growth begins and is about 5-10cm, water regularly but avoid waterlogging. Here at OFF we start off with a weekly water and as the season gets warmer we increate to 1-2x a week. If it has been a more 'wet' season then we refrain from extra waterings. Make sure to water early morning or in the evening to avoid sunburning your dahlia plants during summer.
Staking
Dahlias benefit from staking at planting time to support growth. We use stakes every 2.5m on both sides of our 1m rows, with 15cm gridded netting in two layers - 40cm from the ground and 80cm from the ground.
Feeding
Apply a balanced fertiliser once plants are established. Avoid high nitrogen fertilisers. We use a seaweed feed once a week.
Maintenance
- Pinch out growing tips to encourage bushier plants (once approx 30cm tall)
- Deadhead regularly to promote continuous blooms
- Pick off side flower buds to encouragea bigger, stronger bloom
- Cut deep to influence longer stems
Lifting & Storage
Lift tubers after the first frost:
- Label all of your dahlia clumps at the base of the stem
- Cut stems back and leave in the ground for a week
- Dig the tuber clumps using a garden fork, be careful not to damage tuber clumps by digging too close
- Wash off most of the dirt
- Allow tubers to dry
- Store in a cool, dry place. We like to store ours in tubs that allow ventilation in pine shavings
Optional:
- Divide your tuber clumps into individual tubers / smaller clumps
- Make sure to label each tuber, we use vivid straight onto the tuber
- Make sure to sanitise your snips or knives by using a 10% bleach water solution to prevent any spread of bacterias and/or virus
This is what works best for us here at Ophelia Flower Farm and we recommend you also do your own research and try other methods to find one that best suits your garden.