Alcea Rosea Blacknight

Description

Alcea Rosea Blacknight, commonly known as Blacknight Hollyhock, is a stunning perennial plant that belongs to the mallow family (Malvaceae). It is native to Europe and Central Asia and is widely cultivated for its showy, deep-purple flowers that bloom from late spring to early fall. The plant can grow up to 6 feet tall and 3 feet wide and has a woody stem with large, lobed leaves that are green on the upper surface and light green on the underside.

Taxonomic Information

Appearance

Alcea Rosea Blacknight has striking, deep-purple flowers that can grow up to 4 inches wide. The flowers have a single, central tube that is surrounded by five petals that are ruffled at the edges. The plant blooms from late spring to early fall and produces a large number of flowers that are arranged in a spike-like cluster. The leaves of the plant are large and lobed, with a rough texture on the surface. They are green on the upper surface and light green on the underside. The plant can grow up to 6 feet tall and 3 feet wide, and has a woody stem that is covered in fine, white hairs.

Care Guide

Alcea Rosea Blacknight is a hardy plant that is easy to care for. Here are some tips to ensure that your plant thrives:

• Water: Keep the soil evenly moist, but avoid overwatering as this can lead to root rot. Water deeply once a week during the growing season.
• Fertilization: Fertilize the plant with a balanced, all-purpose fertilizer once a month during the growing season.
• Soil: The plant prefers well-drained soil that is rich in organic matter. Amend the soil with compost before planting.
• Sunlight: Alcea Rosea Blacknight prefers full sun, but can tolerate partial shade.
• Hardiness Zones: The plant is hardy in USDA zones 4-9.

Common Pests & Diseases

Alcea Rosea Blacknight is generally resistant to pests and diseases. However, it can be susceptible to the following:

• Leaf Spot: This fungal disease causes brown spots on the leaves of the plant. To prevent leaf spot, avoid overhead watering and remove infected leaves promptly.
• Japanese Beetle: These beetles can eat the foliage and flowers of the plant. Handpick the beetles or spray the plant with neem oil to control the infestation.
• Aphids: These small insects can suck the sap from the plant and cause stunted growth. Spray the plant with insecticidal soap to control the infestation.

Habitat

Alcea Rosea Blacknight is native to Europe and Central Asia and is widely cultivated as a garden plant. It prefers well-drained soil and full sun, but can tolerate partial shade. The plant is hardy in USDA zones 4-9.

Question and Answer

Q: Can Alcea Rosea Blacknight grow in containers?

A: Yes, Alcea Rosea Blacknight can be grown in containers. Use a large container with drainage holes and fill it with well-drained soil. Water the plant deeply once a week and fertilize it with a balanced, all-purpose fertilizer once a month during the growing season.

Q: How often should I water Alcea Rosea Blacknight?

A: Water the plant deeply once a week during the growing season. Keep the soil evenly moist, but avoid overwatering as this can lead to root rot.

Q: How do I propagate Alcea Rosea Blacknight?

A: Alcea Rosea Blacknight can be propagated from seed or by division. To propagate by seed, sow the seeds in a well-drained soil in the spring. To propagate by division, divide the plant in the spring or fall and replant the divisions in well-drained soil.

Q: How tall does Alcea Rosea Blacknight grow?

A: Alcea Rosea Blacknight can grow up to 6 feet tall and 3 feet wide.

Related Plants

• Alcea Rosea Nigra
• Alcea Rosea Chater’s Double Purple
• Alcea Rosea Chater’s Double Yellow
• Alcea Rugosa

References

• “Alcea Rosea.” Missouri Botanical Garden, www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b438.
• “Alcea Rosea ‘Blacknight’.” Plant Finder, www.monrovia.com/plant-catalog/plants/3125/blacknight-hollyhock/.
• “Alcea Rosea ‘Blacknight’.” RHS Gardening, www.rhs.org.uk/Plants/196700/Alcea-rosea-Blacknight/Details.