Eagle Heights Community Garden mandates organic control of weeds and undesired insects in the gardens. Here are some commonly found pests found at the gardens and approaches to protect your garden from them.


Nothing beats adequately mulching your plot. A 6-inch mat of hay or leaf mulch will deter weeds from sprouting. Mulch will also help preserve soil moisture so you don’t have to water as frequently.

Crab Grass

Remove all the roots including the white stolons while double digging.

Garlic Mustard

Garlic mustard is an invasive non-native plant that is related to mustard greens. The garlic mustard emerges early in the spring and grows to be 3 feet tall with broad triangular shaped leaves with a white compound flower at the top of the spike. Garlic mustard threatens the prairie species and other native understory plants in the areas surrounding the gardens. Please do your part to remove as much garlic mustard as you see by pulling the whole plant including the root before the flowers begin to form.

More garlic mustard information

Wisconsin DNR invasive plants information


Comfrey is planted for it’s flowers and medicinal properties. It’s also a very aggressive weed. Please do not plant comfrey in your plot. Comfrey grows in a mound it has long spade shaped leaves. It has a long tap root that must be completely removed to eliminate the comfrey from regrowing and spreading.

More comfrey information


Peppermint, Spearmint, and Catnip all have stems that have 4 sides. Mint has a shallow root system and will aggressively spread through your garden. If you must plant mint in the gardens, please plant it in a pot so that the roots stay contained.


If not contained the roots of horseradish will spread rampantly and become a pest in the garden. It’s best to plant horseradish in a pot in the ground to keep the roots under control. The roots for a tap root that can grow as deep as 3 feet below the ground surface. In order to control the plant the whole root must be removed.


Mexican Bean Beetles

Mexican bean beetles resemble lady bugs, but they are orange with black spots. They feed on bean leaves and beans. The larvae are yellow with Velcro like hairs.  Wasps can be effective on these pests if the release of the wasps are time correctly and environmental conditions are favorable for the wasps. Otherwise the most effective control method is a combination of row cover and picking adults and larvae and destroying yellowish egg masses from the bottoms of leaves.

Colorado Potato Beetles

Colorado potato beetles emerge from the soil and crawl onto potato leaves to feed and lay their orange eggs on the underside of leaves. They feed on potato leaves and can reduce the yield of potatoes.  BT is effective against these pests, if applied at the correct time. Given the scale of most of the gardens, it is most effective to monitor the plants and pick the beetles into glass jar of water and to destroy the egg masses as they appear.

Cucumber Beetles

Cucumber beetles are yellow and black with stripes or spots. They concentrate in squash and cucumber flowers. They will eat the leaves of squash and cucmber leaves while the plants are getting established. They can carry mosaic virus and will infect squash with the virus.  The best protection from these beetles are to cover the plants with rowcover until the plants begin to flower.

Flea Beetles

Flea beetles range in size from minute to more than 1/4 inch long. Most are dark with a smooth, shiny surface; however, some are striped. Hind legs are enlarged, enabling the beetles to jump vigorously when disturbed. They damage a wide range of vegetables, riddling the leaves with small holes. In the early spring they will eat arugula, mustard, and broccoli into lacey skeletons.  The best protection from these beetles are to cover the plants with row cover until the temperatures warm and the flea beetles begin to die back.

Plant Diseases

Basil Downy Mold

On July 30, 2010, Dr. Brian Hudelson, plant pathologist at the University of Wisconsin in the Plant Disease Diagnostic Clinic, diagnosed downy mildew on basil. This is the first report of this disease on basil in Wisconsin. Basil downy mildew has made recent headlines nationally as a new disease in North America as well as Europe. First reported in FL in 2007, basil downy mildew was later found in field and greenhouse in Canada, Argentina, and in the US states of NC, PA, NJ, NY, MA, NC, KS, and MO in 2008. This disease was found in Eagle Heights Community Garden by A. J. Gevens on July 22, 2011.Basil downy mildew is caused by the fungus-like pathogen Peronospora belbahrii and can be transmitted on seed, infected plant parts, and on the wind. This particular downy mildew can both ornamental and basil varieties grown as herbs. It is suspected that basil downy mildew has moved geographically on contaminated seed or leaves. The spores of basil downy mildew are produced on leaf underside prolifically and can be aerially dispersed long distances. The management of basil downy mildew includes planting uninfested or ‘clean’ basil seed and selecting resistant or tolerant varieties. Minimizing leaf wetness and humidity will aid in downy mildew management as the pathogen is favored by moist conditions (best to water only at base and avoid getting leaves wet). It is known that sweet basil varieties are more susceptible than other basil species (such as purple and small-leafed basils). Air movement around plants should be maximized by removing weeds. Please dispose of diseased leaves and plants by enclosing in plastic and throwing in trash (at home, not in garden). Basil downy mildew symptoms and signs. A. Topside of leaf (note yellowing or chlorosis and brown, dead lesions. B. Underside of leaf (note patches of gray-purple fuzzy pathogen sporulation). Symptoms occur first on lowest leaves.  First Report of Basil Downy Mildew in Wisconsin – A.J. Gevens, Extension Plant Pathologist, Univ. of Wisconsin-Madison, and B.D. Hudelson, Plant Pathologist, Plant Disease Diagnostic Clinic, Univ. of Wisconsin-Madison. (with contribution from M.T. McGrath, Plant Pathologist, Cornell Univ.)