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Corydalis calycosa

corydalis

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This mound-forming perennial is known for its striking, true blue and purple-hued flowers with a white throat, which are sweetly scented and appear in dense racemes during summer. The fern-like, deeply cut bright-green foliage adds an attractive, bushy texture to the plant, making Corydalis calycosa a standout in shaded borders or woodland gardens.

How to care for Corydalis calycosa:

Select a cool, partially shaded location with well-draining, humus-rich soil. Plant in early spring or fall, spacing 15-30cm (6-12in) apart. Maintain consistent moisture, especially during the spring growing season, and apply a 5-7cm (2-3in) layer of organic mulch to retain moisture and keep roots cool. Feed with a balanced, slow-release fertiliser in early spring. Many Corydalis species enter dormancy during hot, dry summers, so reduce watering but don't let roots dry out completely. In autumn, cut back stems to near ground level, doing so earlier if self-seeding is a concern. Monitor for slug and snail damage, especially on young growth.
Flowering period:
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Eventual height:
0.3m
Eventual spread:
0.3m
Position:

Light shade

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.

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RH30007473
9cm pot
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RH30007655
3 × 9cm pots
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