Cow-parsnip
Heracleum sphondylium
Last reviewed: June 2026
Light
part shade
Water
medium
Size
24"–72" H × 12"–36" W
Bloom
May, Jun, Jul
Native to
AZ
Pollinators
bees, beetles, flies
Cow-parsnip is a tall, dramatic biennial with large umbrella-shaped white flower clusters that bloom from May through July. This robust plant can reach up to 6 feet tall with broad, deeply lobed leaves that create a bold textural statement in partly shaded areas.
In an HOA neighborhood
Cow-parsnip takes more care to keep looking intentional in a front yard. Maintenance level: moderate. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Very tall and wild appearance inappropriate for front yards
- Dies back completely in winter leaving bare spots
- Can cause skin irritation similar to giant hogweed
Wildlife value
The large flower clusters attract diverse pollinators including bees, beetles, and flies during the summer months. Seeds provide food for birds and small wildlife.
Common questions
- How much sun does Cow-parsnip need?
- Cow-parsnip grows best in part shade conditions.
- When does Cow-parsnip bloom?
- Cow-parsnip blooms in May, June, and July.
- Where is Cow-parsnip native?
- Cow-parsnip (Heracleum sphondylium) is native to AZ, per the USDA PLANTS Database and regional native plant society lists.
- What pollinators does Cow-parsnip attract?
- Cow-parsnip draws bees, beetles, and flies.
- Is Cow-parsnip HOA-friendly?
- Cow-parsnip 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 Cow-parsnip? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
Not sure where to start? Take the 2-minute yard quiz