How to Build a Rain Garden in Eugene, Oregon
How to Build a Rain Garden in Eugene, Oregon
Create a sustainable landscaping feature that manages stormwater runoff and protects local watersheds by filtering pollutants before they reach the Willamette River.
What You'll Need
- Perc test kit or a steady-state infiltration test
- Native rain garden plants (e.g., Red-osier dogwood, Slough lettuce)
- Organic compost and mulch
- Shovel and garden rake
- Measuring tape and marking paint
Steps
Step 1: Site Selection
Identify a natural depression or a low point in your yard where runoff collects. Ensure the site is at least 10 feet away from your home's foundation and not located directly over a septic system or underground utility line.
Step 2: Conduct a Percolation Test
Dig a hole and fill it with water to see how quickly it drains into the soil. Because Lane County often has heavy clay, this test determines if you need to amend the soil or install an underdrain system to prevent standing water for more than 48 hours.
Step 3: Map and Mark the Basin
Use marking paint or a garden hose to outline the garden's perimeter. The shape should follow the natural flow of water from your downspouts or driveway, typically forming an oval or kidney shape.
Step 4: Excavate the Area
Remove the grass and dig out the soil to create a shallow basin, usually 6 to 12 inches deep. Save the excavated soil to use as a berm on the downhill side to keep the water contained within the garden.
Step 5: Amend the Soil
Mix the native soil with organic compost to improve drainage and nutrient levels. If your soil is predominantly clay, incorporate a high percentage of compost to create a more porous environment for root growth.
Step 6: Install Native Plants
Plant native Oregon species that can tolerate both saturated soil and periods of drought. Place the most water-tolerant species in the center (the deepest part) and more drought-tolerant varieties along the slopes.
Step 7: Apply Mulch
Spread a 2-to-3-inch layer of shredded hardwood mulch or river rock over the soil. This prevents erosion, suppresses weeds, and keeps the soil moist during the dry Eugene summers.
Step 8: Redirect Runoff
Adjust your downspouts or create a shallow swale to direct water into the rain garden. Ensure the water enters the basin slowly to avoid carving deep gullies into your new landscape.
Expert Tips
- Avoid using synthetic fertilizers, as these can wash into the storm drains and contaminate local waterways.
- Choose plants from local nurseries that specialize in Willamette Valley native species for higher survival rates.
- Check with the City of Eugene regarding local stormwater ordinances before starting major grading projects.
See also
- Best Local Bakeries in Eugene, Oregon
- Finding the Best Local Contractors in Lane County, Oregon
- Best Hiking Trails in Lane County, Oregon
- How to Build a Rain Garden in Eugene, Oregon