Do not allow its flowers that are quite white fool you. Well-adapted to warm climates, African rue (Peganum harmala L.) is considered an invasive and noxious weed in several states. Whether an rue grows in your landscape, place on your backyard gloves, then throw the gauntlet down — it is a a monster to destroy. Its deep and extensive root system can endure a eradication try. Do not give up. With persistence, it is possible to kill rue utilizing one of three methods that are successful.
Cut African rue to the floor using a pair of pruning shears. Bag the clippings and discard in the trash. Don’t compost or burn off this plant. Continue mow or to reduce the plant again as it sends up new shoots. This approach might take to eliminate an rue entirely. In the mean time, plant preferred crops to consume water and the nutrients in the soil, helping to starve the rue rapidly.
Cut African rue to the floor and protect the region with three levels of thick, UV-stabilized plastic sheeting. Extend it at least 5 feet beyond where the African rue was developing. Weigh down the plastic with cement blocks or bricks, or secure it. Leave the plastic in place for two years for total eradication.
Spray the foliage with glyphosate — a non-selective herbicide easily accessible to the home gardener — in the late-winter or early spring, just as the plant is forming leaf buds that are new. Reapply every two to a month while it’s still actively developing, utilizing the greatest power that is suggested. Glyphosate kills crops that are dwelling, therefore be cautious not to conquer-spray-on crops that are desirable.