A boulevard garden can greatly enhance your neighborhood with a variety of colorful, fragrant plants, especially if carefully planned and maintained. We encourage new gardeners to start with gardens in their own yards before creating a blooming boulevard (the space between the street and the public sidewalk). A poorly designed boulevard garden can contribute to water pollution rather than alleviate it.
If you've decided to take the plunge, here are a few, simple recommendations for planning a boulevard garden:
- If crowded on-street parking means your boulevard will be used as a frequent pathway, grass might be your best option, or plant clusters of flowers between stepping stone pathways.
- A grass strip is an effective buffer zone on the street side of the garden. It gives people a place to step when they get out of their cars. Use turf or low ground cover like pussy toes along the street.
- A boulevard is a harsh environment - hot, dry and subject to road-salt stress and snow piles. Choose hardy plants, like shorter ornamental and native grasses, that can tolerate boulevard conditions.
- Rain gardens are not permitted on the boulevard, but allowing a shallow 2-3" depression or low swale in the center of the garden will help catch rainwater from the adjacent sidewalk and prevent soil and mulch erosion.
- Planting under trees is not a problem. Their roots spread under sidewalk and lawns. However avoid planting annuals because it disturbs the soil every year, creates more erosion, and potentially harms tree roots. We suggest using woodland plants instead.
- Plants that are too floppy might not have the right aesthetic for urban boulevards. Choose compact perennials that are tolerant to boulevard conditions. For example, wild ginger is appropriate for dry shade.
- Most cities have ordinances regarding maximum heights of boulevard plantings. Most cities limit heights to 30"-36".
- Soil erosion caused by high-crowned boulevard gardens can be a big problem. Use shredded hardwood mulch around plants, keeping the final mulched surface an inch below the curb or sidewalk.
- Before planting a tree in an urban boulevard, a permit must be obtained. In Minneapolis, call the Minneapolis Park and Recreation Board at 612-370-4900. In St. Paul, call the Forestry Office at (651) 632-5129 to request a Forestry Tree Permit.
Before you dig, call Gopher State One Call at 651- 454-0002 or 1-800-252-1166 to have underground utility lines marked. Minneapolis city ordinances No. 427.10 and 427.28 encourage flowers on boulevards, not vegetables or shrubs, with a maximum plant height of 36 inches. If plants are within 20 feet of an intersection, alley or driveway, or within 5 feet of a stop sign or fire hydrant, the maximum height is 18 inches for public safety reasons. A permit is required for non-vegetative materials, e.g., wood, brick or metal. Call 612-673-2403 for more information.
Help! Many boulevard gardens have been planted without considering rainwater issues. If the soil surface is high-crowned or above the level of the curb, soil and mulch can be washed into the gutter and then to our lakes and river. We encourage gardeners to remedy these boulevards. Each garden is unique, and the remedy will depend on your situation.