Overview
Humulus lupulus L. var. lupulus, commonly known as common hop, is a perennial climbing plant that belongs to the family Cannabaceae. The plant is commonly used for its fragrant flowers in making beer and other alcoholic beverages.
Origin and Distribution
The plant originally comes from Europe, Asia, and North America and has been cultivated for over 1,000 years. In the United States, it is widely grown in the Pacific Northwest and other regions.
General Appearance
The common hop plant is a perennial, herbaceous vine that can grow up to 20 feet tall. The plant has annual stems that are covered in rough hairs and can become woody with age. Its leaves are typically large, palmately lobed, and have teeth along the margins. The plant's flowers are cone-shaped and can range in color from pale green to yellow to light brown.
Uses
The most common use of common hop is in the brewing industry, where its flowers are used to add bitterness, flavor, and aroma to beer. Its other uses include herbal medicine, where it is used to treat anxiety and sleep disorders, and as a dietary supplement due to its high flavonoid content. Additionally, the plant is used for ornamental purposes in gardens and landscaping.
Light Requirements
Humulus lupulus L. var. lupulus grows best in full sunlight. It requires at least six hours of direct sunlight daily. Without adequate light, the plant may grow weak and stunted, resulting in smaller yields compared to those grown in full sunlight.
Temperature Requirements
The plant grows well in cool to moderate temperatures. The optimal temperature for growth and development is between 10°C and 25°C. However, Humulus lupulus L. var. lupulus can withstand temperatures as low as -6°C in winter. High temperatures above 25°C during the growing season can cause heat stress, resulting in poor growth and reduced yield.
Soil Requirements
The plant prefers soils that are fertile, deep, and well-draining. The ideal pH range for Humulus lupulus L. var. lupulus is between 6.0 and 8.0. The soil should be rich in organic matter and have good water retention capacity. The plant does not tolerate waterlogged soils, which can lead to root rot. Additionally, the soil should be free from weeds, which can compete with the plant for nutrients and water.
Cultivation methods for Humulus lupulus L. var. lupulus
Humulus lupulus L. var. lupulus, commonly known as hops, are grown mostly in areas with cool summer climates. The plant can tolerate summer temperatures up to 28°C but thrives in cooler climates of about 20°C. Hops require a lot of sunlight, full sun is the best. Anything less may result in a reduced yield. A well-draining nutrient-rich soil with a pH range of 6.0-8.0 is ideal for planting hops.
Watering needs
Hops require a lot of water, especially in their first year of growth. The soil should always be slightly moist, but not water-clogged. In hot weather, hops require plenty of water to help them grow. During the dry season, irrigation should be done regularly, especially if it does not rain for more than three days. Overwatering should also be avoided to prevent root rot.
Fertilization
Fertilization is vital for the growth and yield of hops. A quality fertilizer should be applied in early spring before the growing season begins. Composted manure, bone meal, and fish emulsion are some of the best recommended organic fertilizers for Humulus lupulus L. var. lupulus. Fertilization should also continue during the growing season since hops require a constant supply of nutrients.
Pruning
Pruning is essential in controlling the growth of hops. The plant should be pruned to remain within an acceptable height to make it easy to harvest the hops cones. Pruning should be done in late winter to early spring before the growing season starts. The first year of growth, hops should not be pruned much to allow for healthy root development. In subsequent years, the plants should be pruned back to the soil level to encourage a healthy yield of hops cones.
Propagation methods of Humulus lupulus L. var. lupulus
Humulus lupulus L. var. lupulus, commonly known as the hop plant, is propagated through vegetative and sexual methods. The plant is dioecious, meaning that male and female flowers are produced on separate plants. Therefore, getting a hop plant to flower requires having both male and female plants.
Vegetative propagation
The vegetative propagation method of hop plants involves taking cuttings from existing plants and rooting them to develop new plants. This method ensures the exact genetic copy of the parent plant, so the offspring will have the same characteristics in terms of flavor, aroma, and efficiency.
The best time to take cuttings from a hop plant is during the spring season when the new shoots are emerging. The cuttings should be taken from the base of the plant and should be at least six inches long. The lower leaves should then be removed, and the cutting should be dipped in a rooting hormone before planting in a potting mix.
The cutting should be watered regularly and kept in a warm, humid location until roots emerge, which generally takes around three weeks. Once the roots are apparent, the cutting can be transplanted to its permanent location in the garden or field.
Sexual propagation
The sexual propagation method of hop plants involves growing plants from seeds. This method is more economical than vegetative propagation since it produces a larger number of plants at a time. However, sexual propagation can result in differing characteristics in offspring since genetic variability can occur.
The best time to start the seedlings is in early spring by planting the seed in a potting mix. The seeds should be placed one inch deep in the mix, and the mix should be kept moist but not waterlogged. When the seedlings are around eight weeks old, they can be transplanted into their permanent location.
It is worth noting that hop plants grown from seed will need several years to develop and reach maturity.
Disease Management for Humulus lupulus L. var. lupulus Plants
Humulus lupulus L. var. lupulus plants are susceptible to several diseases that may affect their growth and yield production. These diseases can cause stunted growth, yellowing and browning of leaves, rotting of stems and cankers that can girdle and kill vines. The following are common diseases that may affect the plants:
- Verticillium Wilt: A fungal disease that causes yellowing and wilting of leaves, stunted growth and plant death. The disease can be managed by planting resistant varieties, practicing crop rotation, and avoiding high soil moisture levels.
- Downy Mildew: A fungal disease that causes yellowing of leaves, white mold growth on the underside of leaves, and premature plant death. The disease can be controlled by using copper-based fungicides and improving air circulation around plants.
- Powdery Mildew: A fungal disease that causes white powdery spots on leaves, stems, and flowers, and can affect yield. The disease can be managed by using sulfur-based fungicides and planting resistant varieties.
Pest Management for Humulus lupulus L. var. lupulus Plants
Humulus lupulus L. var. lupulus plants are also susceptible to pests that can cause significant yield losses. The following are common pests that may affect the plants:
- Spider Mites: These pests cause yellowing and bronzing of leaves, reduced plant growth, and a decrease in yield. The pests can be managed by using insecticidal soaps or oils, reducing dust build-up on leaves, and increasing humidity.
- Japanese Beetles: These pests cause skeletonization and defoliation of leaves, decreased yield, and weakened vines. The pests can be controlled by using insecticidal soaps or oils, handpicking, and using pheromone traps.
- Aphids: These pests cause curling and distortion of leaves, stunted growth, and can spread viruses. The pests can be managed by using insecticidal soaps or oils and introducing biological control agents like ladybugs.
Implementing good cultural practices such as pruning to increase air circulation, appropriate irrigation, and fertilizer use can also help prevent and manage diseases and pests in Humulus lupulus L. var. lupulus plants.
