Agastache verticillata Woot. & Standl.
Agastache verticillata Woot. & Standl., also known as Whorled Giant Hyssop, is a plant species belonging to the mint family, Lamiaceae. This species is native to the central part of North America, specifically in the Great Plains regions of the United States and Canada.
Appearance
Agastache verticillata is a perennial herb that typically grows up to 2-3 feet in height. It has a bushy, upright form with square-shaped stems that are slightly hairy and can range in color from green to reddish-brown. The leaves are whorled in groups of three around the stems and are lance-shaped, serrated, and have a rough texture. The flowers are small and tubular, ranging from pink to purple in color, and grow in dense clusters at the top of the stems.
Uses
Agastache verticillata is a popular garden plant due to its attractive foliage and long-lasting flowers, which bloom from mid-summer to early fall. The plant attracts a variety of pollinators such as bees, butterflies, and hummingbirds, making it an ideal choice for pollinator and wildlife gardens. It is also used in herbal medicine for its anti-inflammatory and antispasmodic properties and has been traditionally used to treat colds, coughs, and gastrointestinal ailments.
In addition to its medicinal uses, the leaves of Agastache verticillata are used as a culinary herb, commonly added to teas, soups, and stews to give a slightly sweet, anise-like flavor.
Common Names
Whorled Giant Hyssop is the most common name for this species, but it may also be referred to as Purple Giant Hyssop, Purple Licorice Plant, or Horsemint.
Light requirements
Agastache verticillata Woot. & Standl. requires full sun to partial shade for optimal growth. In areas with intense sunlight, partial shade may be required to prevent leaf scorching. The plant can survive in low light conditions but may not flourish as much as it would in full sun.
Temperature requirements
The typical growth temperature range of Agastache verticillata Woot. & Standl. is between 18-26°C, with a minimum of 10°C. The plant can survive temperatures as low as -20°C in winter. In environments with high humidity, the plant may be susceptible to fungal diseases, and proper ventilation is required to promote growth.
Soil requirements
This plant prefers well-draining soil with a pH range that falls between 6.5 and 7.5. Soil that is too acidic or alkaline can have a negative effect on the plant's growth. Agastache verticillata Woot. & Standl. performs best in moderately fertile soil that is rich in organic matter. The plant can tolerate drought and low soil fertility but will require supplemental watering and fertilizer to promote growth.
Cultivation Methods
Agastache verticillata Woot. & Standl. is a hardy perennial plant that is commonly grown in gardens and landscapes. It is a heat-tolerant plant that prefers full sun to partial shade. It grows best in well-draining soils that are rich in organic matter. The plant can be propagated through stem cuttings or by dividing an adult plant.
Watering Needs
Agastache verticillata Woot. & Standl. requires moderate watering, especially during hot and dry weather conditions. The plant should be watered deeply and regularly, ensuring that the soil is moist but not waterlogged. Overwatering can lead to root rot and other fungal diseases.
Fertilization
Agastache verticillata Woot. & Standl. benefits from fertilization, especially during the growing season. A balanced granular fertilizer with equal amounts of nitrogen, phosphorus, and potassium can be applied every four to six weeks. The plant can also benefit from a layer of compost or well-rotted manure added to the soil around the base of the plant every spring, which helps to improve soil fertility and provide additional nutrients.
Pruning
Agastache verticillata Woot. & Standl. requires minimal pruning. However, if the plant becomes leggy or unruly, it can be cut back to half its height in midsummer to encourage bushy growth and improve its overall appearance. After blooming, the plant can be deadheaded to encourage more blooms and prevent unwanted self-seeding.
Propagation of Agastache verticillata Woot. & Standl.
Agastache verticillata Woot. & Standl., also known as Whorled Giant Hyssop, is a perennial plant that grows in USDA hardiness zones 5 to 9. There are several methods of propagating this plant, including:
Seed Propagation
The most common method of propagating Agastache verticillata is through seeds. Collect the seeds from the plant during the fall, and plant them in a propagating tray filled with well-draining soil and a light cover of vermiculite or sand. The seeds should be kept in a warm (70 to 75°F), humid place until they germinate, which usually takes about 2 to 4 weeks. After germination, move the seedlings into larger pots and continue growing them in a greenhouse or another protected environment until they are large enough to be replanted outdoors.
Cuttings Propagation
Another way to propagate Agastache verticillata is through cuttings. Take cuttings in the early summer, selecting a stem that has not yet flowered and removing all leaves except for the top two sets. Place the cuttings in a rooting hormone and insert them into a propagating tray, filled with well-draining soil. Keep the tray under a misting system to ensure that the cuttings remain moist and don't dry out. Cuttings should root in about 3 to 4 weeks. After rooting, move the cuttings to a larger pot or replant them outdoors.
Division Propagation
Agastache verticillata can also be propagated through division. Dig up the plant during the spring or fall, and gently separate the roots into smaller sections. Replant these sections in new locations, ensuring that each section has a crown and a good root system. Water the new plants well and keep them in a shaded area until they become established.
Disease Management
Agastache verticillata Woot. & Standl. is a resilient plant that is not prone to many diseases. However, two common diseases can still affect the plant, specifically powdery mildew and rust.
Powdery mildew is a fungal infection that appears as a powdery white substance on the leaves. This disease can cause damage to the plant and weaken it over time. To manage powdery mildew, you need to practice good sanitation by removing infected leaves and disposing of them properly. You can also apply a fungicide to the plant in severe cases.
Rust is another fungal infection that usually affects the leaves of Agastache verticillata. It causes yellowish-orange spots on the leaves and can also weaken the plant in the long run. To control rust, it is essential to ensure good air circulation by not overcrowding the plants and keeping the leaves dry. You can use a fungicide to manage it as well.
Pest Management
Agastache verticillata is also relatively pest-resistant. However, several common pests can still affect the plant, including aphids and spider mites.
Aphids are small insects that feed on the sap of the leaves, causing stunted growth and yellowing of the foliage. To manage aphids, you can use insecticidal soap, neem oil, or horticultural oil to suffocate them. It would be best to apply these treatments early in the morning or late in the afternoon to avoid damaging the plant in high heat.
Spider mites, on the other hand, are tiny arachnids that feed on the underside of the leaves. They usually appear when the temperature is hot and dry and can cause leaves to turn yellow or brown. To control spider mites, you can use an insecticidal soap or neem oil and spray them on the leaves to suffocate the mites. You can also introduce natural predators, such as ladybugs or lacewings, to control their population.
