Fertilizer and pesticide use
If you fertilize your lawn, please keep fertilizer off sidewalks, driveways and all other hard surfaces to prevent runoff from entering nearby water bodies — runoff causes increased algae blooms. Minnesota law prohibits the release of fertilizer on hard surfaces such as sidewalks, driveways or the street.
Visit the Minnehaha Creek Watershed District website to learn more about what you can do to keep fertilizer from reaching ponds and lakes.
Guidelines to follow
Don't fertilize unnecessarily
Have your soil tested once every five years to determine whether you need to fertilize. The University of Minnesota sells soil sample test kits for $15. For more information, call 612.374.8400. The Minnesota Extension Service recommends fertilizing lawns no more than three times a year: mid-May, early September and mid-October.
Use weed killers and pesticides sparingly
Apply them only to the trouble spot, not the entire lawn.
Choose a lawn fertilizer without phosphorous
To protect water quality, state law prohibits the use of phosphorus fertilizers on lawns and turf in the Twin Cities metropolitan area. Most soil in St. Louis Park has ample amounts of phosphorus and does not need additional amounts. However, there are exceptions to the law. Phosphorus-containing fertilizer can be applied to residential lawns if:
- A soil test indicates insufficient phosphorus.
- This is the first growing season for new seed or sod.
Make sure the middle number on the fertilizer package (which indicates the amount of phosphorus) is zero. Commercial lawn care services will also provide fertilizers without phosphorus upon request.
Aerate your lawn
Through aeration you reduce the amount of fertilizer and pesticide you need to use. Aeration removes plugs of grass, loosens the soil and promotes healthy root development. Aerated lawns absorb water more quickly and minimize runoff.
St. Louis Park encourages the use of native and alternative landscapes, and has planted them on some city properties. Also called pollinator or sustainable landscapes, alternative landscapes emphasize the use of native plants, including prairie grasses and flowers over turf grass. Native plants require less fertilizers and pesticides and promote native ecosystems, such as bees and other pollinators. Download the city's native vegetation permit and ordinance to learn more about setting up an alternative landscape on your property.
- University of Minnesota - Sustainable urban landscape information series
- North American Pollinator Protection Campaign
Tall grass and noxious weeds
Per St. Louis Park City Code, no lawn in the city may have grass taller than six inches or have noxious weeds on property. The city will send a letter notifying the offending property of the violation with a deadline for compliance. If the deadline passes and there is not compliance, the violation will be corrected at owner's expense.
How to use compost
The best way to improve your soil is to mix in compost. Whether you use compost from your backyard bin, the organics recycling program or purchase commercial compost, there are a variety of ways to use it. Sprinkle compost on top or mix it into your flower or vegetable gardens, gently rake it into tree beds, blend it with potting soil to reinvigorate indoor plants or spread it on top of your lawn.
You should never use 100 percent compost instead of using soil to grow plants, trees, shrubs or grass. Soil with up to 20 percent compost is recommended for most growing needs. The University of Minnesota recommends homeowners use one inch of compost for common landscape projects and garden beds.
Visit the Composting Council's website for compost use instructions and a compost calculator.