Overview
Astragalus flexuosus (Hook.) Dougl. ex G. Don var. greenei (Gray) Barneby, commonly known as Greene's milkvetch or Bent milkvetch, is a herbaceous perennial plant native to western North America. It belongs to the family Fabaceae or legumes and is a member of the genus Astragalus which encompasses over 3,000 species.
Origin and Distribution
Greene's milkvetch is native to western North America, particularly in the United States with a range extending from central California to central Nevada. It mainly grows on arid rocky slopes, sagebrush foothills, and sandy or gravelly flats at elevations ranging from 1500 to 2500 meters.
Common Names
Greene's milkvetch is known by various common names including Greene's milkvetch, Bent milkvetch, and Flexuous milkvetch.
Appearance
Greene's milkvetch is a low-growing perennial herb that typically grows up to 20 cm tall. It has a deep taproot and a spreading habit, with numerous erect or ascending stems that are sparsely to moderately branched. The leaves are composed of numerous small leaflets attached to a central stem, giving the foliage a feathery appearance. The flowers are small and white, pink, or purplish, arranged in a compact cluster on a long stalk, rising from the axil of a leaf. The fruits are legumes that are oblong or broadly elliptical, and minutely hairy.
Uses
Greene's milkvetch has a long history of use in traditional Native American medicine, particularly by the Paiute tribe. They consumed the seeds as a food source and used them to make a poultice to treat swelling and soreness. Nowadays, modern herbalists use the root of Greene's milkvetch to make extracts and tinctures that are taken orally to improve the immune system and relieve symptoms of colds, flu, and respiratory infections. It is also utilized in ecological restoration projects as it contributes to nitrogen fixation, which improves soil fertility and quality.
Light Requirements
Astragalus flexuosus var. greenei favors full sun to partial shade. It grows best in areas where it receives plenty of direct sunlight for at least six to eight hours a day. Without enough light, the plant may become leggy and weak with small leaves and poor blooms.
Temperature Requirements
Grow Astragalus flexuosus var. greenei in a region with an average temperature range of 55 to 70 degrees Fahrenheit. The plant performs best in mild to average temperatures, not too hot nor too cold. Extreme heat and frost can damage and kill the plant.
Soil Requirements
Astragalus flexuosus var. greenei grows in a variety of soils. The plant can tolerate rocky, sandy, or clay soils, but it prefers a well-draining soil with a pH between 6.0 and 8.0. Additionally, the soil should be moderately fertile with good organic content. Improve the soil quality by adding organic matter and fertilizers to enhance the drainage and aeration of the soil.
Cultivation Methods
Astragalus flexuosus (Hook.) Dougl. ex G. Don var. greenei (Gray) Barneby is a herbaceous perennial plant native to the western United States. It grows well in dry, well-draining soil and requires full sun exposure for optimal growth. The seeds of this plant can be sown in early spring, and it can also be propagated through root cuttings or division of mature plants.
Watering Needs
Astragalus flexuosus (Hook.) Dougl. ex G. Don var. greenei (Gray) Barneby is drought-tolerant and does not require frequent watering. However, it should be watered deeply but infrequently during prolonged dry spells to prevent wilting. The soil should be allowed to dry out before the next watering to avoid waterlogging and root rot.
Fertilization
Astragalus flexuosus (Hook.) Dougl. ex G. Don var. greenei (Gray) Barneby can grow in poor soils, but the addition of compost or a slow-release fertilizer can help enhance its growth and flowering. Fertilization should be done in early spring when the plant is actively growing, and it should be repeated every two to three months until fall.
Pruning
Astragalus flexuosus (Hook.) Dougl. ex G. Don var. greenei (Gray) Barneby requires minimal pruning. Dead or damaged stems should be removed to promote new growth and prevent disease. It can be cut back to the ground after flowering to stimulate fresh growth. However, pruning should not be done excessively, as it can stress the plant and reduce its overall vigor.
Propagation of Astragalus flexuosus var. greenei
Astragalus flexuosus var. greenei is native to western North America and is commonly known as Greene's milkvetch. It is a perennial herb that can reach up to 80 cm in height and has small, yellow flowers that bloom from May to August. Here are the different propagation methods for this plant:
Seed Propagation
The easiest and most common way to propagate Astragalus flexuosus var. greenei is through seeds. The seeds can be planted in the spring or fall in well-draining soil. The soil should be moist, but not too wet. The plant prefers full sun or partial shade.
Before planting, the seeds can be scarified. This means that the hard outer coating of the seed is scratched or broken to allow water and air to penetrate the seed coat. This process can be done using sandpaper or a small file.
Once the seeds are planted, it usually takes 2 to 3 weeks for them to germinate. Once they have grown to about 2 inches in height, they can be transplanted into individual pots or directly into the ground.
Vegetative Propagation
Astragalus flexuosus var. greenei can also be propagated through vegetative methods, such as cuttings or division.
Cuttings are taken from the stems of the plant and should be about 4 inches in length. Remove the lower leaves and plant the cutting in moist soil. Keep the soil moist and in a warm, bright place until roots have formed and new growth appears. This generally takes up to 4 weeks.
Division is another method of vegetative propagation. Divide the plant into smaller sections, each with several stems and roots, and replant them in separate pots or outdoors after the last frost. Keep the soil moist until new growth appears.
Regardless of which propagation method you use, make sure to water the new plants regularly and keep the soil moist until they are well-established.
Disease Management:
Astragalus flexuosus var. greenei is generally considered to be disease-resistant. However, some common diseases that affect other members of the Astragalus genus may also affect this plant.
One of the most common diseases that affect Astragalus plants is powdery mildew. Powdery mildew is a fungal disease that can cause white powdery patches on the leaves, stems, and flowers of the plant. To manage this disease, it is recommended to remove any heavily infected plant parts and use fungicides if the infection is severe.
Another potential disease that may affect Astragalus plants is root rot. Root rot is a fungal disease that can cause the roots to rot, leading to stunted growth, yellowing leaves, and plant death. To manage this disease, it is recommended to plant the Astragalus in well-draining soil and avoid over-watering.
Pest Management:
Astragalus flexuosus var. greenei is also generally resistant to pests. However, some common pests that may affect this plant include aphids, spider mites, and thrips.
Aphids are small, soft-bodied insects that can suck the sap from the plant, causing stunted growth and yellowing leaves. To manage this pest, it is recommended to use insecticidal soap or neem oil.
Spider mites are tiny, almost invisible pests that can cause a fine webbing to appear on the plant. They can also cause yellowing leaves and stunted growth. To manage this pest, it is recommended to wash the plant with a strong jet of water, use insecticidal soap, or neem oil.
Thrips are small, slender insects that can invade the leaves and flowers of the plant, causing brown scars and deformation. To manage this pest, it is recommended to use insecticidal soap or neem oil.
