Raingarden Workshops

Unseasonably warm weather, long droughts and flooding rains are the new normal for spring and summer in Minnesota. Learn how your yard can adapt to and even help mitigate threats posed by these extreme weather events.

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Garden Evaluation Criteria

Visual Appeal and Impact

Visual appeal and impact is usually your initial reaction to the overall garden and/or yard. A good example is if you are driving by a house and you see a garden that leaves an impression on you, before you have noted the different aspects of the garden.  These different aspects might include:

Color Interest – Garden has complementary colors, including those of rocks, mulch and other non-plant materials. These colors work well together. 

Interest in texture – This includes texture of plants (hairy, waxy, feathery, spikes, etc.) and landscape materials. Lighting and the presence of shade also can bring out interesting textures in the garden.

 Unique features – Decorative materials that can capture the eye such as pieces of art, water fountains, architectural features and hanging baskets are part of the overall effect a garden has.


Design considers the different aspects of the garden that contribute to its whole. It’s a longer observation. Choice and placement of plants and other materials are two important factors.  Multifunctional gardens also represent good design. They integrate balance, composition and creativity with ecological function. A downspout directed to a dry creek bed leading to a raingarden can be aesthetically pleasing and is multifunctional. Other factors include:

Balance – There is fluidity and symmetry in the design. There is also a variety of height and shape among the plants.

 Composition – The layout complements the surroundings, including the house and neighborhood. For example, the colors of the plants blend with or accentuate the color of the house. This also includes placement of plants and objects in relation to each other.

 Creativity – Some of the features have never been tried or seen before, or are used in new ways. They cause some element of awe in the observer. This could be a unique of choice of plants or decorative materials.

Plant Variety and Health

Perennials – A predominance of perennials over annuals is preferred.  If the varieties selected are well suited to the location – sun/shade/soil and water conditions – this is usually evident by the plant health and/or bloom.  Variety in trees and shrubs add structure to the garden, as well as seasonal interest. Having some annuals can create visual appeal and impact, but they do not add the variety that we are considering here.

Seasonal Interest – This can also be described as interest throughout the growing season. We can only view the current stage of the growing season, but there may be indication of a succession of blooms or other elements that keep the garden interesting and beautiful at all times.


Dedicated maintenance is the key to a beautiful and healthy garden.

Appropriately deadheaded – We prefer deadheads are left alone when they provide food and habitat for wildlife. Some dried plants provide seasonal interest throughout the winter.  Other plants, such as hostas, don’t provide forage and are just unattractive unless the dead material is removed.

Appropriately mulched – freshly mulched in bare areas; mulch may not be necessary if the garden is thickly covered with plants; mulch coverage shouldn’t be too thin or thick – should be around 2 inches – nor should it be placed where it will run off.

No standing water (unless rain in the last 48 hours) – applies only to raingardens. A raingarden is designed to infiltrate within 48 hours. If there is standing water and it has not rained within the last 48 hours, the raingarden is not functioning properly.

Environmental Stewardship

Environmental stewardship is the responsibility to take care of our natural resources to ensure that they are sustainably managed for current and future generations. It includes conservation of biological diversity, forest ecosystem health and vitality, and sustainable maintenance of soil and water.

Turf reduction – We prefer that the yard is at least 50% gardens as opposed to turf grass. However, having turf grass is better than having bare soil. If there is evidence that the homeowner is using environmentally friendly ways to grow turf grass or is following sustainable lawn care practices, it counts in their favor.  Though, admittedly, it is almost impossible to tell unless you see a sign.

Conserve inputs – The garden minimizes the need for water, fertilizer, herbicide and pesticide. For water use, some ways to tell the homeowner is minimizing inputs includes the appropriate placement of native perennials, also the presence of rain barrels, redirected downspouts, and soaker hoses.  Here again, a predominant use of annuals requires many inputs.  Trees provide canopy in a yard and neighborhood, they conserve inputs and are an excellent stormwater feature.

Concave Boulevard – Garden is shaped to allow water to flow into the boulevard and to infiltrate into the ground. There is not a barrier at the sidewalk, such as grass, stone or other edging that prevents the water from flowing into the boulevard. There is no sign of erosion from the boulevard.

Landscape includes a raingarden – A raingarden can sometime be difficult to identify, especially if it is a mature raingarden and surrounded by other plantings.  If you can identify a raingarden onsite, please note it for our records here.

Your donation is an investment in the future of our shared legacy, and will help us improve the health of our urban landscapes.

If you love gardens, clean watersheds and working with your community, join hundreds of others and enjoy the fun!

Metro Blooms Blue Thumb program is a public-private partnership promoting the use of native plants, raingardens and shoreline stabilization to improve water quality.