Origin and Common Names
Humulus lupulus L. ssp. americanus (Nutt.) A. & D. Löve is a subspecies of Humulus lupulus, which is commonly known as hops. This subspecies is native to North America, specifically the central and eastern regions of the United States. Common names for this plant include American hops, wild hops, and eastern hops.General Appearance
American hops are perennial climbing vines that can grow up to 25 feet in height. They have thick, rough stems with small hairs and can attach themselves to structures or other plants through the use of their hooked tips. The leaves are heart-shaped and have toothed edges, with a deep green color. American hops are dioecious, which means they have separate male and female plants. The female plants produce the cone-shaped flowers or hop cones that are used in brewing beer.Uses
The hop cones of American hops are primarily used in the brewing industry to add flavor, aroma, and bitterness to beer. The resins and essential oils found in the hop cones contribute to its unique flavor and aroma profile. In addition to its use in beer, the plant has also been used for medicinal purposes, such as an herbal sedative and as a remedy for insomnia and anxiety. The roots of the plant contain a bitter compound called lupulin, which has been used to stimulate appetite and aid in digestion. Overall, American hops are an important plant in the brewing industry and have a long history of being used for medicinal purposes as well. Its unique appearance and characteristics make it an interesting and valuable addition to any garden or landscape.Light Requirements
The plant Humulus lupulus L. ssp. americanus (Nutt.) A.& D. Löve requires full sunlight for optimal growth. It can tolerate partial shade, but the yield and quality of the plant may be reduced. The plant should be grown in a location where it receives at least 6 to 8 hours of direct sunlight per day.
Temperature Requirements
The plant requires cool temperatures to grow, with average temperatures ranging from 13 to 24 degrees Celsius. The plant thrives in areas with low humidity and temperatures between 15 to 20 degrees Celsius. The plant can withstand cold temperatures if it is dormant, but it cannot tolerate frost.
Soil Requirements
The plant prefers well-drained soils with a pH range of 6 to 7.5. The soil should be rich in organic matter, with good water retention capacity. The plant should not be grown in areas with waterlogged soils, as this can lead to root rot and reduce crop yield. Additionally, the plant requires adequate nutrients, particularly nitrogen, phosphorus, and potassium. Therefore, it is essential to amend the soil with organic fertilizers before planting.
Cultivation
Humulus lupulus L. ssp. americanus (Nutt.) A.& D. Löve, commonly known as American hops, can be grown in well-draining soil with a pH range of 6.0 to 8.0. This plant thrives in sunny locations with partial shade and needs sturdy support systems to hold its height and weight.
Watering Needs
American hops require deep watering, especially during hot and dry weather conditions, to keep the soil moist but not waterlogged. It is essential to water at the base of the plant to prevent the leaves from getting wet as this can cause fungal diseases.
Fertilization
The soil needs to be enriched with organic matter to promote healthy growth. Adding compost or well-rotted manure before planting can provide the necessary nutrients. Fertilizers with high nitrogen content should be used sparingly, as this can lead to excess leaf growth and reduced flower production.
Pruning
Pruning is essential to maintain the shape and size of the plant and to promote optimal flower growth. The best time to prune American hops is in late winter or early spring before new growth appears. Cut away any dead or damaged branches and remove any weak or thin shoots. Leave between 2-4 of the strongest shoots per support wire, based on how vigorous the plant has been growing.
Propagation of Humulus lupulus L. ssp. americanus (Nutt.) A.& D. Löve
Humulus lupulus L. ssp. americanus (Nutt.) A.& D. Löve, commonly known as American hops, can be propagated through various methods such as rhizome division, stem cuttings, and seed germination.
Rhizome Division
Division of rhizomes is the most commonly used method for propagating Humulus lupulus L. ssp. americanus. The best time to perform rhizome division is in early spring when the plant starts to show signs of new growth. The rhizomes should be carefully dug out and then divided into sections each containing at least one bud. The divided rhizomes can then be planted in prepared soil beds or pots.
Stem Cuttings
Stem cuttings can also be used for propagation of Humulus lupulus L. ssp. americanus. The best time to take cuttings is in late spring or early summer when the plant is actively growing. Cuttings should be taken from the tips of young stems, about 5-10 cm long, and should include 2-3 nodes. The cuttings should be dipped in rooting hormone and then planted in a rooting medium composed of a mix of sand and peat. The stem cuttings should be kept moist until they start to develop roots.
Seed Germination
Humulus lupulus L. ssp. americanus can also be propagated using seeds. The seeds need to be stratified for about 2-3 months before planting to help break their dormancy. The stratified seeds should be planted in prepared soil beds or pots in early spring. The soil should be kept moist until the seeds germinate, which usually takes about 2-3 weeks. Seed germination can be unpredictable, and it may take a few attempts to successfully germinate seeds.
Disease Management
Humulus lupulus L. ssp. americanus (Nutt.) A.& D. Löve, commonly known as American hop, can be affected by various diseases that can cause damage to the plant and reduce yield. The common diseases that affect American hop plants include:
- Downy mildew: This disease is caused by Pseudoperonospora humuli. Symptoms include yellow spots on the leaves, which turn brown and necrotic with the growth of the disease. The disease can be managed by planting resistant varieties, keeping the foliage dry, and applying fungicides.
- Powdery mildew: This disease is caused by Podosphaera macularis. Symptoms include white powdery growth on leaves, which can cause defoliation and reduce yield. The disease can be managed by planting resistant varieties, pruning to increase air circulation, and applying fungicides.
- Verticillium wilt: This disease is caused by the fungus Verticillium albo-atrum. Symptoms include yellowing of leaves, stunted growth, and wilting of the plant. The disease can be managed by planting resistant varieties, crop rotation, and avoiding planting in contaminated soil.
Pest Management
American hop plants can also be affected by several pests that can cause significant damage to the plant. The common pests that affect American hop plants include:
- Spider mites: These pests are tiny, sap-sucking insects that cause bronze or yellow spots on leaves. They can be managed by spraying the plant with water or insecticidal soap, removing heavily infested leaves, and releasing natural enemies such as predatory mites.
- Japanese beetles: These pests are voracious eaters, and they can consume the hop foliage, buds, and flowers. They can be managed by handpicking them off the plants, applying insecticides, and using pheromone traps to attract and trap them.
- Hop aphids: These pests suck sap from the plant, causing yellowing of leaves, stunted growth, and wilting. They can be managed by spraying the plant with water or insecticidal soap, releasing natural enemies such as ladybugs and lacewings, and avoiding the use of fertilizers that promote high nitrogen levels.
