PlantFun
Plant Needs
Sunlight
Full sun to partial shade; tolerates dry, nutrient-poor soils with minimal stress
Watering
Water deeply when the top 2–3 cm of soil dries out; drought-tolerant once established
Temperature
Hardy to -10°C; thrives in cool to temperate summer temperatures below 30°C
Characteristics
- Leaf: Narrow lanceolate leaves, pale green, arranged alternately along stems
- Flower: Dense terminal spikes of small, pale yellow, four-petaled blooms
- Stem: Erect, branched stems with fine, soft pubescence
Care Guide
Watering
Water regularly during active growth to support flowering; avoid waterlogging
Fertilization
Optional diluted compost tea once monthly to support growth. No regular fertilization required; avoid high-nitrogen feeds that may reduce flowering
Composted eggshell powder：Sprinkle a thin layer around the base of plants in early spring; avoid direct contact with foliage to prevent potential burningPruning
- Deadhead spent flower spikes to prevent unwanted self-seeding in managed garden spaces
- Cut back stems to ground level after flowering to encourage regrowth in mild, frost-free regions
- Remove damaged or yellowing leaves to improve airflow and maintain plant appearance
Toxicity
Warning: this plant may be toxic.
Pets & Humans
Pets: ASPCA: No known toxicity to cats
Humans: No known toxic effects to humans
Garden Uses & Culture
Culture: Historically valued as a reliable source of bright yellow textile dye in medieval Europe
Usage: Dye production, wildflower garden ornamental, pollinator habitat for bees and butterflies
