Terrace rain gardens and regular rain gardens on private property are two different types of rain gardens. Property owners may also hire a contractor to plant and design or do it themselves.

If a terrace has met design requirements, the rain garden will be constructed in conjunction with the street reconstruction. Residents then select from a number of planting plans which are installed the following spring.

A rain garden on private property typically accepts runoff from roof downspouts and will naturally overflow to the sidewalk or driveway if your yard is sloped in a traditional manner.

Rain gardens in the terrace typically involve a curb cut that allows road water to enter the rain garden. The garden does not “overflow” so much as fill up to a point where no additional road water can enter as the elevation of water in the garden and the street are equal. Terrace rain gardens tend to require more maintenance as the water that comes in from the street carries more dirt than runoff from a roof top.

The outside of the Distributed Green Infrastructure Pilot area the City of Madison only contributes and plants rain gardens that are constructed in the terrace and accept street runoff. Those types of rain gardens are normally constructed as part of a street reconstruction project. In that case, often the Road Contractor will construct the physical garden and a City team will plant it the following spring.

When we arrive with your plants we will:

  • Remove weeds
  • Install native plant plugs
  • Mulch around native plant plugs
  • If necessary, place sandbags on curb cuts to block excess water

The native plants we install will be young. As they settle in and establish their roots they will be vulnerable. Sand bags should be left for the first month to prevent plants from washing out. This step is not necessary for terrace rain basins.

Early Maintenance

During the first month your rain garden will need:

  • Watering twice a week if it has not rained
  • Protection from large water influxes (sand bags)
  • Careful weeding

After a month, sand bags can be removed from curb cut as plants establish their root system. During the first few summers, weeding your rain garden is critical as native plants establish.

Long-term Maintenance

To keep your rain garden healthy over time you should:

  • Remove accumulated dead vegetation. Bonus: doing this in spring rather than fall provides winter habitat for insects and birds!
  • Monitor for excess buildup of sediment in the basin of your rain garden. You can dig around plants and excavate this material if needed.
  • Monitor for drainage. If your rain garden is taking longer than 48 hours to drain or if water is not flowing into your rain garden from the street, first check that the curb cut is free of material and if problems persist, contact us.

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