Origin
Evax involucrata Greene, commonly known as blokus or rayless goldenrod, is a perennial subshrub native to the southwestern region of the United States and northwestern region of Mexico.
Common Names
Besides blokus and rayless goldenrod, Evax involucrata is also known by other common names such as western ditch goldenrod, Holt's goldenrod, smooth goldenrod, and bushy goldenrod.
Uses
Evax involucrata has been traditionally used by Native American tribes, such as the Tohono O'odham, to treat various ailments. The plant contains bioactive compounds that have been demonstrated to possess anti-inflammatory, anti-diabetic, and anti-tumor properties. In addition, the plant's flowers and leaves are also used to make tea, which is believed to have a calming and relaxing effect on the body and mind.
General Appearance
Evax involucrata typically grows to a height of approximately 1 to 3 feet, with a spread of up to 2 feet. The plant bears clusters of flower heads at the top of the stem. The flower heads are typically about 1/4 inch in diameter and are composed of many small yellow flowers. The stems of the plant are green and woody, while the leaves are long and narrow, measuring about 1-3 inches in length. The plant typically blooms from July to September, producing an abundance of bright yellow flowers that can attract a variety of pollinators.
Light Requirements
Evax involucrata Greene thrives well when grown in full sunlight. Therefore, the plant should get exposed to a minimum of six hours of sunlight every day. Inadequate light exposure often results in stunted growth, weak stems, and yellowing of leaves.
Temperature Requirements
The temperature requirements of Evax involucrata Greene vary depending on the stage of growth. During germination, the temperatures should range between 18°C to 21°C. When fully grown, the temperature ranges between 26°C and 30°C, with a nighttime temperature drop of around 10°C. Too much exposure to temperatures beyond the range mentioned results in the stunting of growth, leaf yellowing, and poor flowering.
Soil Requirements
Evax involucrata Greene requires well-drained soil that can support its growth. The soil should be moist but not soggy as that can lead to root rot and eventually death of the plant. A slightly acidic to neutral pH ranging from 6.5 to 7.0 provides the best-growing conditions for the plant. Organic matter can also be added to the soil to improve water retention and promote the plant's growth.
Cultivation of Evax involucrata Greene
Evax involucrata Greene is usually grown from seeds or cuttings. When growing from cuttings, it is advisable to apply rooting hormone to help in the rooting process. The plant thrives in well-draining soils with a pH ranging from 6-8. It is also essential to plant Evax involucrata Greene in an area that receives partial shade to full sun.
Watering Needs of Evax involucrata Greene
Evax involucrata Greene has medium water requirements. It is essential to keep the soil moist but not waterlogged. Overwatering can lead to root rot, while underwatering can cause the plant to wither and die. It is advisable to water the plant deeply once a week or when the soil feels dry to the touch.
Fertilization of Evax involucrata Greene
Evax involucrata Greene requires regular fertilization to boost growth and flowering. It is advisable to use a balanced fertilizer with a ratio of 10-10-10 or 20-20-20. You can also use organic fertilizers such as well-rotted manure or compost. During the growing season, apply fertilizer every two to four weeks.
Pruning Evax involucrata Greene
Pruning helps to shape Evax involucrata Greene and promote bushy growth. It is advisable to prune the plant in the early spring before the growing season begins. Cut back any dead or damaged branches and trim back any overgrown branches. You can also prune the plant to the desired shape and size.
Propagation of Evax Involucrata Greene
Evax involucrata Greene is a perennial plant that typically grows between 30 and 80 centimeters in height. The plant is native to the western United States and is commonly found in California, Nevada, and Oregon. Propagation of Evax involucrata Greene can be done through seed or vegetative methods.
Propagation Methods
Propagation by Seed: Seeds of Evax involucrata Greene are small and light and can be easily dispersed by wind. Sow the seeds indoors in late winter or early spring. The seeds should be sown on the surface of a well-draining potting mix and covered with a thin layer of sand. Keep the soil evenly moist until the seedlings emerge, which can take up to 14 days. Once the seedlings have emerged, you can transplant them into separate pots or directly into the ground.
Propagation by Vegetative Means: Evax involucrata Greene can also be propagated using vegetative means. Take stem cuttings in the early summer when the plant is actively growing. Cut several 4 to 6-inch lengths of stem and remove all but the top few sets of leaves. Dip the cut end of the stem into rooting hormone and plant the stems into a well-draining potting mix. Provide consistent moisture and keep the plants in a warm, sunny location. The cuttings should begin to root within a few weeks and can be transplanted into individual pots or directly into the ground.
Disease and Pest Management for Evax Involucrata Greene Plant
Like any other plant, Evax involucrata Greene is vulnerable to different types of diseases and pests which may cause harm to the plant leading to stunted growth or even death of the plant.
Common Diseases that Might Affect Evax Involucrata Greene
Armillaria Root Rot: Also known as Mushroom Root Rot, this disease is caused by a fungus called Armillaria Mellea. Symptoms of affected plants include stunted growth, yellowing of leaves, and wilting. This fungus thrives in moist and poorly drained soils. To manage this disease, remove all the affected plants and their roots after which you can rotate the crops.
Gray Mold: Also known as Botrytis Blight, this disease is caused by the fungus Botrytis Cinerea. Symptoms include brown spots on the leaves which later turn to gray spots. The disease may also affect the flowers causing them to turn brown and die. To manage this disease, prune affected leaves and flowers, and maintain good air circulation around the plants by spacing them well.
Downy Mildew: This is a fungal disease which causes the leaves to yellow and appear distorted. It is caused by the Peronospora Viciae Fungus and thrives in high humidity and warm temperatures. To manage this disease, maintain proper spacing of the plants and avoid overwatering.
Common Pests that Might Affect Evax Involucrata Greene
Aphids: Aphids are small insects that suck the sap from the plant causing the leaves to yellow and curl up. These insects multiply quickly, therefore, it is advisable to control them as soon as they are spotted. To manage this pest, you can use ladybird beetles which feed on aphids or spray the plants with a solution of water and soap.
Spider Mites: Spider mites feed on the leaves of the plant and cause them to appear bronzed or yellowed. They thrive in hot and dry environments. To manage this pest, you can spray the plants with a solution of water and soap or release predators such as ladybird beetles.
Caterpillars: Caterpillars are the larvae of moths and beetles which feed on the leaves of the plant causing holes. Their excrement may also cause leaves to blacken and die. To manage this pest, you can handpick them or use Bacillus Thuringiensis which is a natural insecticide.
With proper care and prevention measures, you can protect your Evax involucrata Greene plant from diseases and pests and ensure a healthy growth.
