Knotweed 'Alba' – Persicaria amplexicaulis ‘Alba’ | ↕10-25 cm | Ø9 cm

Bistort ‘Alba’
Persicaria amplexicaulis ‘Alba’

Persicaria amplexicaulis ‘Alba’ is an elegant, long-flowering perennial with slender, pure white flower spikes that rise above the fresh foliage from summer to deep autumn. The plant brings airiness, movement, and brightness to the border and is ideal for natural, lush plantings.

Features and care:

Latin name: Persicaria amplexicaulis ‘Alba’
Dutch name: Bistort ‘Alba’
Height: 10–25 cm (young plants)
Mature height: 80–120 cm
Width: 60–90 cm
Foliage: Large, fresh green, elongated and slightly wavy
Flowers: Slender, pure white flower spikes
Flowering period: July to October
Growth habit: Upright, bushy, and very strong
Light requirement: Sun to light shade
Soil: Moist to moderately moist, rich in humus and well-draining
Moisture: Prefers a cool soil; does not tolerate prolonged drought
Pot size: Ø9 cm, ideal for group planting or as a solitary in a lush border
Pruning: Remove old flower spikes after flowering for a neater appearance. Cut back old stems in spring.
Watering: Water regularly during dry spells. A consistently moist soil promotes the best growth.
Fertilization: In spring, add a layer of compost or organic fertilizer for vigorous growth.
Hardiness: Very hardy. The foliage dies back in winter but re-sprouts vigorously in spring.
Is Persicaria amplexicaulis ‘Alba’ toxic? No, this plant is not toxic to humans, dogs, or cats.

Why choose Persicaria amplexicaulis ‘Alba’?

• Pure white flower spikes for a fresh, light appearance

• Very long flowering, well into autumn

• Strong, reliable, and low-maintenance

• Perfect for natural, lush borders

• Attractive to bees and butterflies