Origin
Phacelia viscida (Benth. ex Lindl.) Torr. is a species of flowering plant in the borage family Boraginaceae, originally found in the western United States and northern Mexico.
Common Names
Phacelia viscida is commonly known as sticky phacelia, sticky scorpion-weed, and balsam phacelia.
Uses
The plant has been traditionally used by Native American tribes as a medicinal herb for treating various ailments such as coughs, colds, and wounds. It is also used as a food source by hummingbirds and bees. The leaves and flowers of the plant are edible and can be used in salads or as a garnish. Farmers also use the plant as a cover crop to improve soil quality and prevent erosion.
General Appearance
Phacelia viscida is an annual herb that grows up to 1m tall. The plant has hairy stems and leaves and produces clusters of small, bell-shaped, lavender-colored flowers. The flowers bloom from May to July, and the plant prefers well-drained soils in open spaces at elevations between 50-8500 ft.
Light Requirements
Phacelia viscida grows best in full sun to partial shade. It requires at least six hours of direct sunlight to grow and thrive. The plant can tolerate some shade but will not develop flowers as quickly or prolifically as those grown in full sun. Therefore, it is recommended to plant this species in areas that receive adequate sunlight.
Temperature Requirements
The plant grows well in areas with mild temperatures. It can tolerate some frost and short periods of drought successfully. However, extended periods of extreme heat or cold can be detrimental to the plant's growth. The ideal temperature range for Phacelia viscida is between 15°C to 25°C (59°F to 77°F).
Soil Requirements
Phacelia viscida grows in various types of soil, including well-draining soils, sandy soils, and clay soils. Still, it prefers well-drained soils with a pH range of 6.0-7.5. The plant can tolerate some soil salinity but not excessive levels. Therefore, it is essential to avoid planting this species in areas with high soil salinity levels. Additionally, the plant can benefit from nutrient-rich soils supplemented with ample organic matter to support its growth and development.
Cultivation Methods for Phacelia viscida
Phacelia viscida (Benth. ex Lindl.) Torr. is a hardy plant species that is relatively easy to grow under the right conditions. The plant thrives in well-drained soil and can grow in full sunlight or partial shade. The ideal soil pH for growing Phacelia viscida is between 6.0 to 7.5.
It is best to sow Phacelia viscida seeds in late winter or early spring when soil temperatures start to warm up. You can either plant the seeds directly into the ground or start them indoors and transplant them outdoors when they are about four to six weeks old.
The seeds should be planted at a depth of about 1/8 to 1/4 inch and spaced about 6 to 12 inches apart. They should then be covered lightly with soil and watered gently. It is important to keep the soil moist during germination, which can take anywhere from one to three weeks.
Watering Needs for Phacelia viscida
Phacelia viscida requires regular watering to grow and stay healthy. However, excessive watering can lead to root rot and other diseases. It is essential to find the right balance of moisture when watering this plant.
A good practice is to water the plant deeply once a week. This will allow the water to reach the roots and help them establish. It is important to avoid watering the plant's leaves or flowers to prevent disease.
Drought-tolerant, Phacelia viscida can survive periods of limited water supply, but it is best not to allow its soil to get completely dry.
Fertilization of Phacelia viscida
Phacelia viscida does not require a lot of fertilization. However, to promote healthy and vibrant growth, you can add a balanced fertilizer to the soil before planting the seeds, at the beginning of the growing season.
A general rule of thumb is to add about 1/4 to 1/2 cup of fertilizer per 100 square feet of soil. This should be worked into the soil to a depth of about 4 to 6 inches. Avoid over-fertilizing the soil as this can lead to excessive leaf growth and reduced flowering.
Pruning Phacelia viscida
Pruning Phacelia viscida is not necessary, but it can help promote denser growth and keep the plant looking neat and tidy. Deadheading or removing spent flowers regularly can encourage the plant to produce more blooms. This is best done during the growing season.
When the growing season comes to an end, you can cut back the plant to about an inch above the ground. This will help the plant to regrow in the following season.
It is important to remember that Phacelia viscida is a self-seeding plant. If you wish to avoid having too many plants, you can remove some of the flowers before they have a chance to produce seeds.
Propagation of Phacelia viscida
Phacelia viscida can be propagated through various methods such as seeds, cuttings, divisions, and layering.
Seeds
The easiest and most common method for propagating P. viscida is through seeds. The seeds should be planted in well-draining soil that has been amended with organic matter. The optimal time for planting is in the spring after the last frost. Sow the seeds on the surface of the soil and cover them lightly with a thin layer of soil. Water the seeds regularly until they germinate. It can take up to 15-30 days for the seeds to germinate.
Cuttings
P. viscida can also be propagated through stem cuttings. Take a stem cutting from a healthy plant that is about 4-6 inches in length. Remove the lower leaves, leaving only the top two or three leaves. Dip the cut end of the stem in a rooting hormone and plant it in a soilless potting mix. Keep the soil moist and provide indirect light until the cutting takes root. This process can take a few weeks.
Divisions
Another method for propagating P. viscida is through division. This method is best done in the spring before new growth has started. Dig up the entire plant and carefully divide the root ball into sections. Each section should have a healthy shoot and an adequate root system. Plant each division in a well-draining soil and water it thoroughly.
Layering
P. viscida can also be propagated through layering, although this method is not commonly used. Select a low-growing branch and make a small cut on the underside of the stem. Gently bend the stem down and bury the wounded section in the ground. Keep the soil moist until roots form, then cut the stem from the parent plant and transplant it to a new location.
Disease and Pest Management for Phacelia Viscida
As with any plant, proper disease and pest management is an essential part of maintaining a healthy and productive Phacelia viscida crop. While this species is generally hardy, a range of pests and diseases can impact its growth and productivity. Below, we describe some common issues and suggest ways to manage them.
Common Diseases
Phacelia viscida is susceptible to a range of fungal and bacterial diseases. One of the most common is powdery mildew, which appears as a white, powdery coating on the leaves and stems. This can be managed by reducing humidity, increasing airflow around the plant, and applying a fungicide. Another common disease is root rot, which can be caused by overwatering or poor drainage. To manage this, allow the soil to dry between waterings and ensure proper drainage.
Leaf spot is another disease that can affect the foliage of Phacelia viscida. This appears as small, dark spots on the leaves and can be managed through the removal of infected leaves and the application of a copper-based fungicide.
Common Pests
Several pests can impact the growth and productivity of Phacelia viscida. Some of the most common include aphids, spider mites, and caterpillars. Aphids are small, pear-shaped insects that suck the sap from the plant, causing stunted growth and distorted leaves. These can be managed through the application of insecticidal soap or neem oil. Spider mites are tiny pests that also suck plant sap, causing yellowing and dropping of leaves. To manage these, increase humidity around the plant and apply a miticide. Caterpillars, such as the cutworm, can also damage the foliage of Phacelia viscida and can be managed by handpicking, applying a biological pesticide, or introducing natural predators such as parasitic wasps.
Finally, it's important to note that proper cultural practices, such as crop rotation, use of disease-resistant varieties, and sanitation, are essential for preventing the spread of disease and pests in any agricultural setting.
