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C. rupestris growth habit

Asteraceae

A fine-leafed species with small, bright yellow flowers that blooms for most of the summer. Plant is a bit weedy-looking and might benefit with some trimming. Not for the formal, tidy garden.

Plant Type: perennial

Plant Form or Habit: rounded/mounded

Plant Use: In beds and borders.

Propagation:

seed

Flower Color:

yellow

Bloom Period:

early summer
mid-summer
late summer

Width: Minimum: 12 inches     Maximum: 24 inches

Foliage Texture: fine

USDA Hardiness Zone: 5

Water Requirements: average

Additional Comments: We also tried growing Centaurea ruthenica, another yellow knapweed, but it did not survive our test-plot conditions.