Description of Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz, commonly known as the Black-flower phacelia, is a small annual plant that belongs to the waterleaf family Hydrophyllaceae. It is endemic to California and can be found in the southwestern United States and northern Mexico. Specifically, it grows in high elevation habitat types such as subalpine forests, coniferous forests, and montane chaparral habitats.
General Appearance
The Black-flower phacelia typically grows up to 10-50 cm tall and has a spread of 15-25 cm. The plant has small alternate leaves that are simple, oblong, and deeply lobed. The inflorescence is a coiled, one-sided cyme, and the flowers are funnel-shaped and measure around 1 cm across. The plant's most defining feature is its dark purple to almost black flowers, which bloom from May to August.
Common Names
The Black-flower phacelia is commonly known by the following names: Black-flower scorpionweed, Black-flower phacelia, Purple-flower scorpionweed, and Purple-flower phacelia.
Uses
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz is primarily used for its ornamental value as a garden plant due to its unique and striking appearance. The plant also serves as a source of nectar for native bees and other pollinators. Additionally, some Native American tribes used the plant for its medicinal properties, using it to treat ailments such as respiratory issues, skin conditions, and rheumatism.
Light Conditions
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz typically grows well in full sun or partial shade. It is adaptable to a range of light conditions but prefers bright light for optimal growth. In low light conditions, it tends to stretch towards the light source, resulting in a weak plant. Therefore, it is essential to provide adequate light to promote healthy growth and development.
Temperature Requirements
The plant grows well in a range of temperatures but thrives in warm conditions. Summer temperatures between 65°F and 75°F are ideal for optimal growth and development. Temperatures over 90°F can cause stress to the plant, resulting in stunted growth and poor flowering. In the winter, it can survive freezing temperatures as low as 20°F without being damaged, making it a hardy plant for cold climates.
Soil Needs
The Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz prefers well-draining soils. It can adapt to a variety of soil types, but it grows best in loamy and sandy soils with a slightly acidic pH between 6.1 and 6.5. The soil should be rich in organic matter and should not be too compacted. A mix of sand and compost can be added to the soil to improve drainage and nutrient availability.
Cultivation methods
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz thrives in dry, rocky soils and areas with high exposure to sun. It grows well in well-drained soils, but cannot tolerate standing water. The plant can be propagated using seeds, which should be sown directly into the soil in the spring. Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz requires minimal maintenance once established.Watering needs
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz is drought-tolerant and requires minimal watering once established. Watering should be reduced during the dormant season to prevent root rot and other fungal diseases caused by excessive moisture. When watering, thoroughly saturate the soil to promote deep root growth.Fertilization
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz does not require regular fertilization. However, if you want to improve soil fertility for other nearby plants, apply a low-nitrogen fertilizer in the early spring. Avoid over-fertilizing as this can lead to excessive foliage growth at the expense of flower production.Pruning
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz does not require regular pruning. However, you can deadhead the faded flowers to encourage the growth of new flowers and to prolong the blooming season. Deadheading also prevents the plant from reseeding excessively. Cut back any stems that have become leggy or overgrown to maintain the plant's shape.Propagation of Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz
Propagation for Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz can be done through several methods. Here are some of the propagation methods:
Seed Propagation
Seed propagation is the most common method for propagating Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz. The seeds should be sown in the early spring when the temperature is mild. These seeds should be lightly covered with soil and should be placed in an area with ample sunlight. They should be kept slightly moist until they germinate. Once the seedlings have grown big enough, they can be transplanted to their permanent locations.
Cuttings Propagation
Cuttings propagation is another way to propagate Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz. To do this, cuttings from the parent plant should be taken in the spring or early summer. These cuttings should be approximately four inches long and must include at least two leaves. The cutting should be placed in a growing medium that is moist and ideally covered with a plastic bag to maintain high humidity. Once the cuttings have rooted, which should take a few weeks, they can be transplanted to their permanent locations.
Division Propagation
Division propagation is also an option for Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz. This method involves digging up the parent plant and dividing it into several sections. Each section must have roots and stems. Once divided, these sections can then be replanted to their permanent locations. This method is best done in the early spring or late fall.
Disease Management
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz is generally a healthy plant. However, certain environmental conditions favour the growth of diseases such as:
- Phytophthora root rot: This disease is caused by a soil-borne fungus that results in wilting and death of the plant. To manage this disease, avoid over-watering, use well-drained soil and avoid planting in areas with standing water.
- Verticillium wilt: This disease is caused by a soil-borne fungus that results in yellowing and wilting of leaves. To manage this disease, remove infected plants and the surrounding soil and avoid replanting the same species in the same area.
- Powdery mildew: This disease is caused by a fungus that results in a white powdery coating on leaves. To manage this disease, maintain good air circulation around the plant, avoid overhead watering and use resistant varieties of the plant.
Pest Management
Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz may be infested by pests such as:
- Aphids: These pests suck plant sap and may cause stunted growth. To manage them, use insecticidal soap or oil or hose the plant down with water.
- Caterpillars: These pests eat the leaves of the plant and may cause defoliation. To manage them, handpick them off the plant or use Bacillus thuringiensis (Bt).
- Spider mites: These pests suck plant sap and may cause yellowing and wilting of leaves. To manage them, hose the plant down with water or use insecticidal soap or oil.
It is always important to monitor plants for signs of diseases or pests so that they can be managed effectively. Timely application of management strategies will help maintain the vigour and yield of Phacelia crenulata Torr. ex S. Wats. var. funerea J. Voss ex Munz.
