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Amsonia 'String Theory'

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Compact and easy to grow, this low-maintenance perennial offers fine, thread-like foliage and pale blue, starry flowers that appear in late spring. Upright and densely clump-forming, it’s ideal for sunny borders or prairie-style planting schemes.

Amsonia 'String Theory' stays smaller than other types, with a tidy, bushy habit. The dark green summer foliage stays clean and healthy and turns a bold golden-orange in autumn, adding seasonal colour. It’s heat and humidity tolerant, copes with some drought once established, and is reliably deer resistant.

Useful for mixed borders, naturalistic planting or low-intervention spaces.

How to care for Amsonia String Theory:

When planting Amsonia incorporate some well-rotted compost or manure and mycorrizal fungi into the planting hole. If the plants are starting to look floppy after they have flowered, they can be cut back to new basal foliage.

Alternatively, they can be given a lighter trim, cutting them back to form neat domes. Once established, lift and divide in spring or autumn.
Flowering period:
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Eventual height:
0.5m
Eventual spread:
0.9m
Position:

Full sun

Rate of growth:

Average

Soil:

Moderately fertile, moist, well-drained soil

Hardiness:

Fully hardy

  • InformationThis perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.

Product options

Product options image
RH30008094
9cm pot
£12.99
available to order from autumn
Unavailable
1
Delivery options (pick your preferred option at checkout)
Standard Delivery£5.99
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