This is a list of undomesticated or feral plants, generally considered weeds, yet having some positive effects or uses, often being ideal as companion plants in gardens.
Beneficial weeds can accomplish a number of roles in the garden or yard, including fertilizing the soil, increasing moisture, acting as shelter or living mulch, repelling pests, attracting beneficial insects, or serving as food or other resources for human beings.
Despite its "sting", young plant parts are edible, as is much of the plant when blanched or otherwise prepared. It can be used to make herbal tea
Also once grown as a crop for its fiber. Its juice was once used in the place of rennet in cheese-making. It was also a source of "green" for dye. It can still be used as a high-protein additive in animal feed, once dried. Nettles prefer soils rich in nutrients beneficial to other plants—particularly nitrogen and phosphorus—and thus can be useful indicators of soil quality.[3]
Domesticated mustard is a hybrid of three different species of wild mustard, all of which are still used in some places for food. This is known as the Triangle of U.
This includes the feral multiflora rose, brought to the US [5] both for use as root stock for domesticated roses, and as a "natural fence" for livestock. In the mid 20th century miles of multiflora rose hedge were planted in sequence.
Used in traditional herbal medicine throughout the world. The common dandelion (Taraxacum officinale) contains chemicals that are known to have diuretic properties.[6]
Dandelions benefits nearby plants through their powerful tap root system. It breaks up hard soil, going deep into the ground, then brings up nutrients other plants could not reach.
Used in traditional herbal medicine to "cleanse the blood" and contains micronutrients that may help with gout
Do not grow around tomato plants, clover is a legume that makes the soil too fertile. Tomato plants need a mild nitrogen deficit to set fruit
Clover, like most legumes, hosts bacteria that fix nitrogen in the soil, helping fertilize nearby plants. Clover also provides ground cover, helping retain water in the soil as a "living mulch", and protecting nearby crops from predation by insect pests. Bare earth gardening makes it easier for insects to home in on plants to destroy, the green of the clover prevents this.
Shepherd's purse—leaves are edible and often sautéed or blanched.
Watercress—can be eaten raw or cooked; is considered a weed in some cultures (caution required when harvesting wild because of the risk of contracting potentially fatal liver fluke).
Habitat for beneficial insects
Wild blackberry—attracts predatory insects, and produces berries.
Peterson, L.A. & Peterson, R.T. (1999). A Field Guide to Edible Wild Plants: Eastern and central North America. Houghton-Mifflin.
Duke, J.A., Foster, S., & Peterson, R.T. (1999). A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America. Houghton-Mifflin.
Gibbon, E. (1988). Stalking the Wild Asparagus. Alan C. Hood & Company.
Sharma, O.P., R.C. Lavekar, K.S. Murthy and S.N. Puri (2000). Habitat diversity and predatory insects in cotton IPM: A case study of Maharashtra cotton eco-system. Radcliffe's IPM world textbook. Minnesota University, USA.
