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Build your own rain garden

Step 1:

Do I need a rain garden?

To determine this you must ask yourself the following questions. If you can answer yes to any one or more of these questions or concerns you should consider the possibility of building a rain garden.

  1. Do I have standing water?
  2. Do I have erosion?
  3. Am I concerned about the amount of water that is entering the storm water system from my property?
  4. Am I concerned about the environment?
  5. Am I looking to incorporate wildlife into my yard?

Step 2:

What kind of rain garden do I want?
  1. A permanent pond
  2. A garden that could hold water when necessary
  3. What type of plants do I want? (native or ornamental)

Step 3:

Consider Possible locations
  1. Where can I put my rain garden? They can be placed at any of the problem areas mentioned above in step 1 as long as it is 10 feet away from the foundation of your house.

Step 4:

Size matters
  1. Determine your roof area
  2. Consider the soil type
  3. Determine the amount of rain water that you want it to hold.

Sizing Tips
Size of Rain Garden Relative to Roof Area for Different Soil Types
  Sand Silt Clay
% of Roof Area 20% 30% 60%


Step 5:

  1. Shape of the depression
  2. Consider type of plants and arrangement that they will be put in. (Put the more aquatic plants where most standing water will be.)

Step 6:

  1. Can I afford it?*
  2. How much of the labor will I be able to do myself?

*Native species rain gardens will be more inexpensive than ornamental rain gardens.

Cost Tips

The following costs may not apply to all rain gardens. The cost will vary depending on how much work you do yourself and the types of plants you want. (Native plants are cheaper than ornamentals and they are more beneficial for the local wildlife).

Construction $3.00/sq. ft.
Design $1.00/sq. ft.
Planting $3.00-$4.00/sq. ft.
Plants $2.50-$4.50/sq. ft.
Total cost $11.00-$13.00/sq. ft.

Cost tips are courtesy of Roger Bannerman of the
Wisconsin Department of Natural Resources.

Step 7:

Site Preparation
  1. Do it yourself
  2. Hire an excavator
  3. Do soil testing to determine what type of soil you will be working with to better accommodate size and types of plants.

Step 8:

Plant it
  1. Plant seeds or plants where appropriate for each individual species depending on water level and flow.
  2. Remember green side up for plants and seeds to only be 1/4 to 1/2 inch deep in soil.

Step 9:

  1. Weeding
  2. Removal of dead plants
  3. Hand clipping
  4. Removal of dead stems

Step 10:


Remember—this is supposed to be fun!