Amethystea

Description

Amethystea is a flowering plant that belongs to the mint family, Lamiaceae. It is also known as the purple giant hyssop or Agastache ‘Amethyst’ and is native to North America. This herbaceous perennial plant can grow up to 4 feet tall and has a spread of 2 to 3 feet. It is a popular choice for gardeners due to its unique color and shape.

Taxonomic Information

Domain	Eukaryota
Kingdom	Plantae
Phylum	Spermatophyta
Class	Magnoliopsida
Order	Lamiales
Family	Lamiaceae
Genus	Agastache

Appearance

Amethystea has long, slender spikes of tiny, tubular flowers that bloom in late summer and early fall. The flowers are usually purple, although they can sometimes be pink or white, and they are arranged in dense, terminal spikes. The leaves are fragrant, lance-shaped, and dark green in color. They are arranged in pairs along the stem and have serrated edges. The stem is square in shape and can be either green or purple.

Care Guide

Amethystea requires well-drained soil that is rich in organic matter. It prefers full sun but can tolerate partial shade. It needs to be watered regularly, especially during hot, dry periods. Fertilize the plant once a month during the growing season with a balanced fertilizer. It is hardy in zones 5 to 10 and can be grown as an annual in colder areas.

Common Pests & Diseases

Amethystea is generally a hardy plant, but it can be susceptible to powdery mildew, rust, and spider mites. To prevent these problems, keep the plant well-watered and ensure good air circulation. If necessary, treat with an appropriate fungicide or insecticide.

Habitat

Amethystea is native to North America, where it grows in prairies, meadows, and open woods. It prefers well-drained soil and full sun but can tolerate some shade.

Question and Answer

Q: How often should I water Amethystea?
A: Water the plant regularly, especially during hot, dry periods.

Q: What is the best fertilizer for Amethystea?
A: Fertilize the plant once a month during the growing season with a balanced fertilizer.

Q: What is the hardiness zone for Amethystea?
A: It is hardy in zones 5 to 10 and can be grown as an annual in colder areas.

Q: What pests and diseases are common in Amethystea?
A: Powdery mildew, rust, and spider mites can be problematic. Keep the plant well-watered and ensure good air circulation, and treat with an appropriate fungicide or insecticide if necessary.

Related Plants

• Agastache foeniculum
• Agastache rugosa
• Agastache mexicana
• Agastache aurantiaca

References

• “Agastache ‘Amethyst’.” Missouri Botanical Garden, www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b489.
• “Agastache ‘Amethyst’.” Plant Finder, www.gardencrossings.com/plantname/Agastache-Amethyst.
• “Agastache ‘Amethyst’ (Purple Giant Hyssop).” Gardenia, www.gardenia.net/plant/agastache-amethyst-purple-giant-hyssop.