News » Hairy Bittercress Control

04/01/2024 - Lawn Care, Organic Gardening

Hairy Bittercress

We have seen a lot of these weeds in our Rhode Island gardens and lawns this spring.

Cardamine hirsuta, also known as hairy bittercress, is a small, annual or biennial weed native to Europe and Asia, but it has spread to many other parts of the world, including North America. It is a member of the mustard family (Brassicaceae). Key characteristics include:

Leaves: Hairy bittercress has a basal rosette of pinnately compound leaves with rounded leaflets. The leaves are alternate on the stem and have a slightly hairy appearance. Stems: The weed has slender, erect stems that grow up to 20 cm tall. The stems are usually hairless and may be branched. Flowers: Small, white, four-petaled flowers develop in clusters at the top of the stems. Each flower is about 3-5 mm in diameter. Fruit: The plant produces slender, elongated seed pods called siliques, which are about 2-3 cm long. When mature, these pods split open explosively, dispersing the seeds over a wide area. Seeds: The seeds are small, oval-shaped, and reddish-brown in color. Growth habit: Hairy bittercress is a cool-season weed that germinates in the fall or early spring, flowers in the spring, and sets seed before dying off in the summer heat.

This weed is commonly found in moist, disturbed soils in gardens, lawns, and along paths or sidewalks. It can be a nuisance due to its rapid growth and prolific seed production, which allows it to spread quickly and outcompete desirable plants.

Like many weeds hairy bittercress has some value.

Hairy bittercress is edible and is sometimes considered a wild edible green. The leaves, stems, and flowers have a peppery, mustard-like flavor similar to watercress, which is a close relative. The plant is rich in vitamins A and C, as well as minerals like potassium and calcium.

Here are some ways to use hairy bittercress in cooking:

Salads: The young leaves and stems can be added to salads for a peppery flavor. Pesto: Blend the leaves with garlic, nuts, cheese, and olive oil to make a flavorful pesto. Soups: Add the leaves to soups or stews for a peppery kick. Sandwiches: Use the leaves as a garnish or green in sandwiches. Stir-fries: Toss the leaves and stems into stir-fries for added flavor and nutrients.

However, it is essential to keep the following precautions in mind:

Proper identification: Ensure that you have correctly identified the plant as hairy bittercress before consuming it, as some wild plants may be toxic. Pesticides: Avoid eating hairy bittercress from areas that may have been treated with herbicides or pesticides. Moderation: While edible, consume hairy bittercress in moderation, as eating large quantities of any wild plant may cause digestive issues for some people. Allergies: If you have allergies to other members of the mustard family, such as broccoli or cabbage, you may also be sensitive to hairy bittercress.

Natural Control Methods

Mulching: Apply a thick layer of organic mulch, such as bark chips or straw, around desired plants. This will suppress weed growth and prevent bittercress seeds from reaching the soil and germinating. Hand weeding: Regularly pull out hairy bittercress plants by hand, ensuring that you remove the entire root system to prevent regrowth. This is most effective when the plants are small and before they set seed. Proper lawn maintenance: Mow your lawn regularly and at the proper height to prevent bittercress from establishing and spreading. A dense, healthy lawn will also outcompete weeds. Soil solarization: Cover the affected area with a clear plastic sheet during the hottest part of the summer, which will heat the soil and kill weed seeds. Planting ground covers: Use dense ground covers in garden beds to shade the soil and prevent bittercress from growing. Corn gluten meal: This natural pre-emergent herbicide can be applied to lawns and gardens to prevent bittercress seeds from germinating.

Remember, persistence is key when controlling hairy bittercress, as it produces numerous seeds that can remain viable in the soil for several years.

Give Atlantic a call to help control this weed in your landscape.