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Dahlia imperialis

dahlia

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This towering, tree-like perennial can reach up to 3m and it needs a long growing season to reach flowering height. If you fancy a change from sunflowers, why not have a go at growing this impressive, long-stemmed, and highly floriferous pink tree dahlia? Great fun to grow, why not pop one or two tubers in your basket and take the plunge? One last thing, if growing as a cut flower, you may wish to have a step ladder handy!

How to care for Dahlia imperialis:

Plant Dahlia imperialis outside after frost, or start off in pots under glass in late winter to early spring. Plant them horizontally approximately 12cm deep, making sure the growing points (‘eyes’) are uppermost. Allow plenty of room between each tuber so the plants can grow and spread to their full size without being overcrowded. While in growth, provide a high-nitrogen liquid feed each week in June, then a high-potash fertiliser each week from July to September. Stake with a cane if it becomes necessary (it may be worth installing a sturdy stake when planting to avoid root disturbance). In mild areas, leave them in situ over winter, but protect the crown with a generous layer of dry mulch. In colder areas, carefully lift and clean the tubers once the first frosts have blackened the foliage and allow them to dry naturally indoors. Then place the dry tubers in a shallow tray, just covered with slightly moist potting compost, sand or vermiculite and store in a frost-free place until planting out again.
Flowering period:
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Eventual height:
3m
Eventual spread:
1.5m
Position:

Full sun

Rate of growth:

Fast-growing

Soil:

Moderately fertile, moist, well-drained soil

Hardiness:

Borderline hardy (will need protection in winter in colder areas)

  • InformationThis bulb dies back after flowering each year and enters a period of rest ahead of regrowth the following season.
  • InformationHumans/Pets: Ornamental bulbs - not to be eaten

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BU30003122
1 × tuber
£5.99
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(shipped within 1-2 working days)
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BU30003237
3 × tubers
was £17.97 now £15.00
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(shipped within 1-2 working days)
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Delivery options (pick your preferred option at checkout)
Standard delivery Bulbs (only)£4.95
Nominated delivery Named Day Delivery£10.95

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