Origin
Phaseolus coccineus L. var. albus (Alef.) Bailey, commonly known as white runner bean, is a plant species originally from South America, specifically from the Andes of Peru, Columbia, and Venezuela.
Common Names
The plant is commonly referred to as the white runner bean, as well as scarlet runner bean, white flowering bean, and white creeper bean.
Uses
The white runner bean is primarily grown for its edible seeds, which can be used fresh, dried, and canned. The beans are rich in protein, fiber, and essential minerals, making them a healthy addition to meals. Additionally, the plant's foliage and flowers can be used decoratively in gardens.
General Appearance
The white runner bean is a climbing plant that can reach heights of up to 10 feet. It has a slender stem with twining tendrils that allow it to climb walls or other nearby plants for support. The leaves are large and heart-shaped, with a light bluish-green color. The white runner bean produces attractive white flowers in clusters, which bloom from mid-summer to early autumn. The plant's fruit is a long, straight pod that contains seeds that are white in color and kidney-shaped.
Light Requirements
Phaseolus coccineus L. var. albus (Alef.) Bailey, or white runner bean, grow best in full sun or partial shade. These plants typically require at least 6-8 hours of sunlight per day to thrive. In areas with intense heat, partial shade may be needed to protect the plant from heat stress.
Temperature Requirements
White runner beans grow best in warm weather. They require a minimum soil temperature of 60°F (15.5°C) for germination, and a daytime temperature between 70-80°F (21-27°C) for optimal growth. However, they can still grow well in cooler temperatures between 50-60°F (10-15.5°C) as long as the soil remains moist.
Soil Requirements
White runner beans prefer well-draining soils that are rich in organic matter. A pH level between 6.0-7.5 is optimal for the growth of these plants. Additionally, they require consistent moisture to avoid stress and promote healthy growth. It is recommended to add compost or other organic matter to the soil prior to planting to provide proper soil nutrition.
Cultivation Methods
Phaseolus coccineus L. var. albus (Alef.) Bailey, commonly known as runner bean, can be grown as a perennial or annual plant. It thrives in areas with well-draining soil, good air circulation, and full sunlight. The plant prefers a soil pH of 6.0 to 7.5 and requires a temperature range of 10-25°C(50-80°F). It can be propagated by sowing seeds directly into the ground in early spring when the soil temperature is above 10°C.
Watering Needs
Runner bean plants need regular watering to help them establish a healthy root system. During the early growth stage, they require around 2 inches of water per week. As the plant matures, its water needs increase to 3-4 inches per week. However, overwatering the plants can cause root rot, so it's crucial to monitor the soil moisture level and avoid excessive watering.
Fertilization
Proper fertilization is essential for the healthy growth of Phaseolus coccineus L. var. albus (Alef.) Bailey plants. A balanced fertilizer containing nitrogen, phosphorus, and potassium is recommended. Fertilizer application should be done at planting time and every three to four weeks during the growing season. It's essential to follow the fertilizer manufacturer's instructions to prevent over-fertilization, which can harm the plants.
Pruning
Runner bean plants require little pruning. However, it's beneficial to pinch out the tips of the plant when it reaches about six feet to encourage bushy growth and improve yields. Additionally, pruning off dead or diseased leaves and stems can help prevent the spread of diseases and pests, promoting healthy plant growth.
Propagation of Phaseolus coccineus L. var. albus (Alef.) Bailey
Propagation is the process of reproducing new plants from existing ones. There are several methods of propagating plants. Some plants can be propagated by seeds, while others require vegetative methods. Phaseolus coccineus L. var. albus (Alef.) Bailey, also known as the white runner bean, can be propagated by either seeds or vegetative methods.
Propagation by Seeds
Seeds are the most common method of propagating most plants, and Phaseolus coccineus L. var. albus (Alef.) Bailey is no exception. The seeds of this plant can be directly sown into the soil or started indoors and then transplanted. The seeds should be sown in well-draining soil and watered regularly. Germination typically occurs within 7-14 days. Once the seedlings have grown their first true leaves, they can be transplanted into their permanent location.
Propagation by Vegetative Methods
Vegetative propagation involves using a portion of an existing plant to create a new one. There are several methods of vegetative propagation, including cuttings, layering, and division.
Cuttings involve taking a portion of the stem or leaf and planting it in soil or water until roots develop. Phaseolus coccineus L. var. albus (Alef.) Bailey can be propagated by stem cuttings that are 4-6 inches long. The cuttings should be planted in well-draining soil and kept moist until roots develop.
Layering involves bending a portion of the stem to the ground and covering it with soil until roots develop. This method can take several weeks or months, depending on the plant. Once roots develop, the new plant can be separated from the parent plant and transplanted.
Division involves separating a portion of the plant, usually the roots, and planting it in its own location. This method can be used for plants that have multiple stems or a clumping growth habit. It is recommended to divide plants in the spring or fall before new growth appears.
Common Diseases of Phaseolus coccineus L. var. albus (Alef.) Bailey
Plant diseases are a major concern for farmers and gardeners. Some of the common diseases that could affect Phaseolus coccineus L. var. albus (Alef.) Bailey include:
- Anthracnose: This disease is caused by the fungus Colletotrichum lindemuthianum and causes circular spots on the leaves, stems, and pods. The spots become sunken and turn brown or black with time, and the entire plant may eventually wilt and die.
- Rust: Rust is caused by the fungus Uromyces appendiculatus and is characterized by the appearance of reddish-brown pustules on the underside of leaves, stems, and pods. The upper side of the leaves usually turns yellow and falls off prematurely, and the yield may be significantly reduced.
- Mosaic: This viral disease is spread by aphids and causes a mottled yellowing of the leaves, stunted growth, and reduced yield. There is no cure for mosaic, so prevention is key.
Pest Management for Phaseolus coccineus L. var. albus (Alef.) Bailey
In addition to diseases, pests such as insects and rodents could also cause significant damage to the plants. Some of the pests that could impact Phaseolus coccineus L. var. albus (Alef.) Bailey include:
- Aphids: These tiny, soft-bodied insects feed on the sap of the plant and can transmit viral diseases such as mosaic. They can be controlled by spraying with insecticidal soap or neem oil.
- Spider mites: These small arachnids feed on the undersides of leaves and cause yellowing, stippling, and eventually, defoliation. They can be controlled by spraying with a fine mist of water to dislodge them or using insecticidal soap or neem oil.
- Cutworms: These larvae of several species of nocturnal moths cut the stems of young plants at soil level, causing them to wilt and die. They can be controlled by using physical barriers around the plants or applying insecticides containing Bacillus thuringiensis (Bt).
- Rodents: Rodents such as mice and rats can feed on the seeds and young plants, causing significant damage. They can be controlled by using physical barriers such as wire mesh around the plants or using rodenticides.
Preventive measures such as crop rotation, maintaining good hygiene around the plants, and using disease-free seeds can help to minimize the impact of pests and diseases on Phaseolus coccineus L. var. albus (Alef.) Bailey. Regular monitoring of the plants for any signs of pests or diseases is also key to successful management.
