Black Mustard
Brassica nigra
Last reviewed: June 2026
Light
full sun
Water
low
Size
24"–60" H × 12"–24" W
Bloom
Jun, Jul, Aug, Sep
Native to
WA
Pollinators
bees, butterflies, beetles
Browse plants for this ecoregion
Black mustard is a tall annual herb that produces clusters of small yellow flowers from summer through fall. It grows quickly to form an upright, branching plant that can reach 5 feet tall in favorable conditions.
In an HOA neighborhood
Black Mustard takes more care to keep looking intentional in a front yard. Maintenance level: high. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Non-native invasive species
- Can look weedy and unkempt
- Self-seeds aggressively
Wildlife value
The flowers attract bees, butterflies, and beneficial beetles throughout the long blooming season. Seeds provide food for birds in late fall.
Common questions
- How much sun does Black Mustard need?
- Black Mustard grows best in full sun conditions.
- When does Black Mustard bloom?
- Black Mustard blooms in June, July, August, and September.
- Where is Black Mustard native?
- Black Mustard (Brassica nigra) is native to WA, per the USDA PLANTS Database and regional native plant society lists.
- What pollinators does Black Mustard attract?
- Black Mustard draws bees, butterflies, and beetles.
- Is Black Mustard HOA-friendly?
- Black Mustard takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Ready to grow Black Mustard? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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