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Dahlia 'Purple Gem'

semi-cactus dahlia

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Dahlia ‘Purple Gem’ is a tuberous-rooted perennial with mid-green foliage and striking cactus-style flowers from mid-summer to the first frosts. Its rich purple blooms, up to 12 cm (4.7in) across, have quilled, spiky petals that deepen in colour towards the centre, carried on strong burgundy-purple stems.

An excellent, popular cultivar, it brings bold structure and long-lasting colour to borders, especially when paired with pinks, purples, and dark maroons. Thriving in full sun and moist, well-drained soil, it also makes a superb cut flower. Pinching young shoots promotes bushiness, while deadheading prolongs the display.

How to care for Dahlia Purple Gem:

Dahlia tubers can be planted outside after frost, or started off in pots under glass in late winter to early spring. Plant them horizontally approximately 12cm deep, making sure the ‘eyes’ are uppermost. Allow enough room between each tuber so the plants can grow and spread to their full size without being over-crowded.

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 canes or brushwood if it becomes necessary. 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:
1.2m
Eventual spread:
0.5m
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)

  • InformationHumans/Pets: Ornamental bulbs - not to be eaten

Product options

Product options image
BU30000133
1 × tuber
£5.99
available to order from winter
Unavailable
Product options image
BU30001359
3 × tubers
£16.50 £5.50 each
available to order from winter
Unavailable
1
Delivery options (pick your preferred option at checkout)
Bulbs (only)£4.99

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