- Tubers
- Wait until after frosts to plant the tubers. An easy way to remember is to plant them in the ground two weeks either side of Melbourne Cup day. You can still enjoy earlier blooms if you start them in pots.
- Potted
- In cold climates they may experience some die back, they will reshoot when weather warms. Ideally wait until after frost before planting out. You can pot them on at any time.
- Botanical Name
- Dahlia x hybrida
- Family
- Asteraceae Plant Type: Tuber
- Size (HxW)
- Tubers: 80-150 x 50-100cm. Dwarf Foliage: ‘Happy Days’: 20-40cm x 20- 40cm. ‘Mystic’: 50-80cm x 40-60cm.
- Depth & Spacing
- Lie the tubers lengthways with the ‘eyes’ (growing tips) pointing up and cover with 5-10cm of soil.
- Tubers
- space 50-100cm apart depending on variety and type of planting.
See above for Dwarf Foliage varieties spacing.
- Soil
- Humus rich, moist, well drained soil is ideal. Improve poor soils with some well rotted manure/compost prior to planting – Dahlias are hungry plants.
- Aspect
- Full sun to semi shade
- Climate
- Cool to Sub Tropical
- Frost
- Half hardy – hard frost and moist soils during dormancy can damage the bulbs, if in doubt they can be lifted.
- Water
- After planting, wait until you see growth before you begin watering – if they are too wet before they initiate growth it can leave them open to rot. Keep moist in active growth. Foliage
- Dahlias
- In pots be sure to water regularly, potting mix is perfectly drained so they need a bit of extra attention with container growth.
- Fertiliser
- Dahlias grow quickly and flower abundantly so are heavy feeders, we recommend applying a well balanced fertiliser prior to planting. If they are left in the ground each year, top dress in winter and summer. A tomato fertiliser is a good choice.
- Foliage Dahlias
- A liquid fertiliser every two to three weeks during growth is ideal.
- Flowering Time
- Summer to autumn (December to April as a rough guide). Foliage Dahlias are already up and growing so will flower earlier this year.
- After Flower Care
- Remove spent flowers to encourage further flowering. We recommend you lift them every year if your ground freezes hard or the soil will be damp in dormancy.
Store tubers during winter in a dry airy position. Plant again anytime from June to November (unless your ground freezes). Tubers left in soggy ground may rot.
- Notes
- The taller varieties, and the Dinner Plates may need staking, doing this at the time of planting will avoid root disturbance later on.
Keep plants well ventilated to avoid mildew.
Don’t be concerned if you have a small tuber, it will set roots more quickly than large tubers and establish easier. The larger tubers have a pre-existing food storage so will form roots a little later, taking longer to establish. The size of the tuber can also depend on the variety, all our Dahlias are of flowering size. Any concerns get in touch we are happy to help, don't forget we guarantee all we sell.
You can pinch your plants when they reach around 20cm with four sets of leaves, snip off the top main stem and it will encourage more lateral buds (this will delay flowering by a week or two but you will have more blooms). To increase the size of the flowers, nip out the side buds as soon as they appear.
When the plants have finished flowering, cease watering, to allow the tubers to mature.
- Foliage Dahlias
- Tubers will be smaller than full size Dahlias but can receive the same care as above. If they have been grown in pots they need to be well cared for to ensure good bulb growth, containers have limited nutrients and water so they appreciate a bit of extra love and attention.