Least Willow
Salix rotundifolia
Last reviewed: June 2026
Least Willow is listed as toxic to grazing livestock (cattle, sheep, and goats) at a slight level by the USDA PLANTS Database (opens in new tab). This is a livestock indicator and is separate from pet toxicity.
Light
full sun
Water
high
Size
36"–120" H × 36"–120" W
Bloom
Apr, May, Jun
Native to
ID, MT, WY
Pollinators
bees, beetles
Round-leaf willow is a shrub that forms a dense, rounded shape with distinctive circular leaves. It produces catkins in spring and requires consistent moisture to thrive. This willow works well as a natural screen or in rain gardens where its high water needs can be met.
In an HOA neighborhood
Least Willow 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.
- Large mature size may appear overgrown
- High water requirements seem excessive for xeriscaping
- Bare winter appearance lacks structure
Wildlife value
The spring catkins provide early-season nectar for bees and beetles when few other plants are blooming. Birds often use the dense branching for nesting sites.
Common questions
- How much sun does Least Willow need?
- Least Willow grows best in full sun conditions.
- When does Least Willow bloom?
- Least Willow blooms in April, May, and June.
- Where is Least Willow native?
- Least Willow (Salix rotundifolia) is native to ID, MT, WY, per the USDA PLANTS Database and regional native plant society lists.
- Is Least Willow toxic to livestock?
- Least Willow is listed as toxic to grazing livestock such as cattle, sheep, and goats (slight severity) by the USDA PLANTS Database. This is separate from pet (dog and cat) toxicity.
- What pollinators does Least Willow attract?
- Least Willow draws bees and beetles.
- Is Least Willow HOA-friendly?
- Least Willow 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 Least Willow? 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