Undergreen Willow: A Hardy Native Shrub for Wet Spots
If you’ve been scratching your head about what to plant in that perpetually soggy corner of your yard, let me introduce you to the undergreen willow (Salix commutata). This unassuming but incredibly useful native shrub might just be the solution you’ve been looking for – especially if you’re dealing with challenging wet conditions that make other plants throw in the towel.
What Makes Undergreen Willow Special?
The undergreen willow gets its charming common name from its distinctive leaves, which are green on top and pale whitish-green underneath. It’s a perennial shrub that typically grows as a multi-stemmed woody plant, usually staying under 13-16 feet tall, though most specimens you’ll encounter are much more modest in size – around 3 feet at maturity.
What really sets this willow apart is its incredible adaptability to wet conditions and its rapid growth rate. While many plants sulk in waterlogged soil, the undergreen willow absolutely thrives in it.
Where Does It Come From?
This hardy native calls northwestern North America home, naturally growing across Alaska, western Canada (Alberta, British Columbia, Yukon, and Northwest Territories), and several northwestern U.S. states including Idaho, Montana, Oregon, and Washington. As a true North American native, it’s perfectly adapted to our climate and supports local ecosystems.
Why You Might Want to Plant It
Here are some compelling reasons to consider adding undergreen willow to your landscape:
- Wetland warrior: This shrub is classified as Obligate Wetland in most regions, meaning it almost always occurs in wetlands – perfect for those challenging wet spots
- Rapid establishment: With its fast growth rate, you won’t be waiting years to see results
- Pollinator support: Early spring catkins provide crucial nectar and pollen when few other plants are blooming
- Erosion control: Excellent for stabilizing wet, erosion-prone areas
- Cold hardy: Thrives in USDA zones 2-6, handling temperatures as low as -38°F
- Low maintenance: Once established, it’s remarkably self-sufficient
Perfect Garden Situations
Undergreen willow shines in specific landscape scenarios:
- Rain gardens and bioswales
- Wetland restoration projects
- Streamside and pond edges
- Naturalized or wild garden areas
- Areas with poor drainage where other plants struggle
- Wildlife-friendly landscapes
Growing Conditions and Care
The undergreen willow is refreshingly straightforward to grow, provided you can meet its basic needs:
Soil: Prefers fine to medium-textured soils and can handle pH levels from 5.0 to 7.3. It has no tolerance for salty conditions, so avoid areas with salt spray or saline soils.
Water: This is where the undergreen willow really shows its personality – it loves water! With low drought tolerance, it needs consistent moisture and actually prefers wet conditions that would drown many other plants.
Light: Grows well in full sun to partial shade, making it quite versatile for different garden locations.
Climate: Needs at least 120 frost-free days and annual precipitation between 20-200 inches, making it well-suited to the Pacific Northwest and similar climates.
Planting and Propagation Tips
Getting started with undergreen willow is easier than you might think:
- Propagation: The most reliable method is through cuttings rather than seeds
- Spacing: Plant 320-1,280 per acre depending on your goals (closer spacing for faster coverage)
- Root depth: Ensure soil allows for at least 12 inches of root development
- Timing: Plant during the dormant season for best establishment
Potential Considerations
While undergreen willow is generally well-behaved, there are a few things to keep in mind:
- It has a relatively short lifespan compared to trees, so consider it a medium-term landscape solution
- The growth form is described as thicket forming, so it may spread more than you initially expect
- It’s not suitable for dry gardens or xeriscapes due to its high water requirements
- Some sources note slight toxicity, so keep this in mind if you have curious pets or children
The Bottom Line
If you’re dealing with wet, challenging areas in your landscape – or if you’re creating habitat for wildlife and pollinators – the undergreen willow deserves serious consideration. It’s a hardworking native that asks for little beyond adequate moisture and rewards you with rapid growth, early-season pollinator support, and effective erosion control.
While it might not win any beauty contests, sometimes the most valuable plants are the ones that simply get the job done reliably, year after year. In the right spot, undergreen willow could become one of your landscape’s most dependable performers.
