Origin and Common Names
Phacelia patuliflora (Engelm. & Gray) Gray var. teucriifolia (I.M. Johnston) Constance, commonly known as tansy-leaved phacelia, is a species of plant in the borage family (Boraginaceae). It is native to North America, specifically the southwestern United States and northern Mexico.
General Appearance
Tansy-leaved phacelia is a herbaceous annual plant that can grow up to 60 cm tall. It has finely divided leaves that are deeply lobed and often have a fern-like appearance. The flowers are arranged in coiled spikes that can be up to 30 cm in length. The flowers themselves are tubular in shape and range from pale lavender to deep blue in color.
Uses
Tansy-leaved phacelia is primarily grown as an ornamental plant in gardens and landscapes. It is also sometimes used as a cover crop in agriculture due to its ability to control weeds and improve soil health. Additionally, some native North American tribes have used the plant for medicinal purposes, such as treating fever and headaches.
Light Requirements
Phacelia patuliflora var. teucriifolia prefers full sun exposure and requires at least 6 hours of direct sunlight daily for optimal growth. The plant can tolerate partial shade conditions, but too much shade may cause stunted growth and reduced flowering.
Temperature Requirements
The plant can thrive in a wide range of temperatures, but optimal growth occurs at temperatures between 18-30 degrees Celsius. Phacelia patuliflora var. teucriifolia can withstand temperature fluctuations but is vulnerable to frost and extreme heat conditions. Winter temperatures below 5 degrees Celsius may cause plant damage, especially if the soil is excessively moist.
Soil Requirements
The plant prefers well-draining soils rich in organic matter. A pH range of 6.5-7.5 is ideal for optimal growth. Phacelia patuliflora var. teucriifolia is moderately tolerant of saline soils and can grow in various soil types, including sand, silt, and loam. Poorly drained soils may lead to root rot and other fungal diseases.
Cultivation Methods
Phacelia patuliflora var. teucriifolia is a hardy plant and can grow in a range of soil types. However, it prefers well-draining soil that is rich in organic matter. It thrives in full sun but can tolerate some shade. The ideal temperature for growth is between 60°F and 80°F. Plant the seedlings in the garden after the frost season has ended. Since this plant self-sows, it can also spread and grow on its own.
Watering Needs
Phacelia patuliflora var. teucriifolia requires regular watering in the initial growth stage. After that, it can tolerate drought conditions and can do well if you water it once a week. It is best to water the plant in the morning and avoid watering late in the day. Too much water can be detrimental to the plant's growth, leading to yellowing of leaves and root rot.
Fertilization
Phacelia patuliflora var. teucriifolia is not a heavy feeder. However, adding compost or well-decomposed manure during planting can improve soil quality. Fertilization can be done once a month during the growing season using a balanced fertilizer with a 10-10-10 NPK ratio. Alternatively, you can use a slow-release fertilizer once every three months.
Pruning
Phacelia patuliflora var. teucriifolia does not require much pruning. Deadheading flowers once they fade can encourage new blooms. If the plant has become too tall, prune it in late summer to maintain its shape. Cut it back to about half of its height. Do not prune at other times of the year, as it can hamper growth and flowering.
Propagation of Phacelia patuliflora var. teucriifolia
Phacelia patuliflora var. teucriifolia can be propagated by seeds, division, or cuttings.
Seed propagation
Seeds can be sown indoors or directly in the garden bed. Indoors, sow the seeds in pots 6-8 weeks before the last frost. The seedlings can be transplanted outdoors once they are 3-4 inches tall and there is no more frost. In the garden bed, sow the seeds once the soil has warmed up in the spring. Sow the seeds just below the surface, and water regularly until the seedlings emerge.
Division propagation
Phacelia patuliflora var. teucriifolia can also be propagated by division. Divide the plant in the spring, just as new growth is beginning. Use a sharp knife or garden shears to carefully divide the plant into smaller sections. Make sure each section has a few strong roots, and replant immediately.
Softwood cutting propagation
Phacelia patuliflora var. teucriifolia can be propagated by softwood cuttings taken in the spring or early summer. Take 3-4 inch cuttings from the tips of the plant's branches, and remove the lower leaves. Dip the cuttings in rooting hormone and plant them in a well-draining potting mix. Keep the soil moist and the cuttings in a warm, bright spot that is protected from direct sunlight. Roots should begin to form in 2-3 weeks.
Disease Management
Phacelia patuliflora var. teucriifolia is subject to various fungal pathogens, including downy mildew, powdery mildew, and anthracnose. Prevention is normally the most effective means of disease management. Remove infected plants parts and use fungicides if necessary.
Pest Management
Phacelia patuliflora var. teucriifolia attracts various insects, such as aphids, spider mites, and thrips. Regular inspection of plants is important for preventive pest management and early detection. Use mechanical and biological controls to manage infestations. Insecticides should be the last resort.
