Japanese indigo (Persicaria tinctoria)

Japanese indigo

Also known as: Dyers Knotweed

The outline is very similar to Inuta, but the eye becomes indigo when the leaves are damaged. The stem is 60 to 90 cm high and branches well. The leaves have a wide lanceolate shape (the tip is sharp like a bamboo leaf, and the base is slightly wider).

Scientific classification

Species

Japanese indigo (Persicaria tinctoria)

Pinks, cacti, and allies

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Annual

Lifespan

2 cm to 5 cm

Flower Size

Pink

Flower Color

Deciduous

Leaf type

20 - 35 ℃

Ideal Temperature

Images of Japanese indigo

Distribution of Japanese indigo

Distribution Map

Japanese indigo is indigenous to regions of Eastern Asia and has established itself in parts of Europe and East Asia. This plant has been introduced and now thrives in temperate to subtropical areas, adapting to a range of environmental conditions in its extended range.

Native

Cultivated

Invasive

Introduced

No species reported

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Care Guide for Japanese indigo

Every week

Water

Full sun

Sunlight

20 - 35 ℃

Ideal Temperature

Water: Japanese indigo thrives in humid environments and prefers consistent soil moisture, requiring weekly watering for optimal hydration. While it has moderate drought tolerance, water management during dry spells is crucial for its vigorous development, especially as an outdoor herbaceous plant influenced by rainfall patterns.

Fertilize: For optimal growth, japanese indigo thrives on quarterly applications of high-phosphorus fertilizers, diluted as per label instructions. Adjust fertilization during active growth, using a balanced, slow-release formula. Monitor japanese indigo closely to prevent nutrient burn, ensuring vibrant foliage and blooms.

Pruning: Japanese indigo, valued for its blue dye, thrives with selective pruning in early to late spring. Remove dead or diseased stems to enhance growth, shape the plant, and improve air circulation. Clean, sharp tools ensure precise cuts, while avoiding excessive pruning prevents stress and stunted growth.

Propagation: Japanese indigo is a vibrant herb valued for its dye. Propagate by surface-sowing seeds in well-draining soil, ensuring bright light and regular misting for moisture. Once seedlings are strong, transplant carefully to avoid root shock, promoting healthy growth.

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