PlantFun
Plant Needs
Sunlight
Full sun to partial sun; thrives in open, unobstructed growing conditions with direct sunlight for most of the day.
Watering
Keep soil evenly moist during germination and seedling stages; reduce watering once established to avoid waterlogged roots.
Temperature
Tolerates light frost during early growth; performs best in cool temperate climates with daytime temperatures between 10–20°C.
Characteristics
- Leaf: Basal rosette of lobed, hairy leaves; stem leaves are smaller, clasping the stem.
- Flower: Dense clusters of four-petaled cruciform bright yellow blooms with a faint honey scent.
- Stem: Erect, branched, and covered in fine, stiff hairs.
Care Guide
Watering
Water deeply once weekly during active growth and flowering
Fertilization
Apply composted manure at planting time. Avoid high-nitrogen fertilizers to prevent excessive leaf growth at the expense of seed production.
Eggshell powder topdress：Crush fully dried eggshells into fine powder; sprinkle 1–2 tbsp around the base of each plant to boost soil calcium levels without introducing odors.Pruning
- Thin overcrowded seedlings to 15–20 cm spacing to improve airflow and light penetration.
- Remove spent flower heads to prevent unwanted self-seeding if not growing for seed harvest.
- Trim yellowing or damaged basal leaves to maintain plant health and reduce pest habitat.
Toxicity
Warning: this plant may be toxic.
Pets & Humans
Pets: ASPCA lists Brassica rapa as non-toxic to cats; no reported adverse effects.
Humans: No acute toxicity; excessive ingestion may cause mild digestive upset due to naturally occurring goitrogens.
Garden Uses & Culture
Culture: N/A
Usage: Oilseed crop for edible cooking oil; livestock forage; ornamental wildflower for pollinator gardens.
