Description of Phaseolus lunatus L.
Phaseolus lunatus L., commonly known as the Lima bean, is a leguminous plant that belongs to the family Fabaceae. The Lima bean is native to Central and South America and was domesticated more than 6,000 years ago. It is a warm-season crop that thrives in tropical and subtropical regions.
Common Names
The Lima bean has various names in different parts of the world. It is commonly called the butterbean in the southeastern United States, chadra or pallar in Peru, frijol de mantequilla in Mexico, haricot de Lima in France, and habichuela or frijol Peruano in the Spanish-speaking countries.
Uses
Phaseolus lunatus L. is mainly used for its edible seeds. The seeds are commonly cooked and consumed as a vegetable, either fresh or dried. They can be boiled, steamed, fried, or baked, and are often added to salads, soups, stews, and casseroles. The Lima beans are also used to make bean burgers, veggie patties, and hummus. Additionally, the plant is used as a cover crop, green manure, and fodder for livestock.
General Appearance
The Lima bean is a climbing or bushy annual plant that can grow up to 3 meters tall. It produces elongated pods that are flat, curved, or constricted, and can have a length of 3 to 15 cm. The pods contain 2 to 4 seeds that are round, oval or kidney-shaped, and can measure up to 2 cm in length. The seeds come in different colors, ranging from white, cream, yellow, green, to purple and black. The leaves of the plant are trifoliate, with each leaflet having a length of 5 to 15 cm. The flowers are white, pink, or violet, and are produced in clusters.
Light Requirements
The Phaseolus lunatus L. plant requires full sun exposure to thrive. It is recommended to place the plant in an area where it can receive at least six hours of direct sunlight each day. If grown indoors, the plant must be placed near a south-facing window or under fluorescent lights for at least 12-16 hours each day.
Temperature Requirements
The ideal temperature range for Phaseolus lunatus L. growth is between 18°C and 29°C. The plant is intolerant to frost and requires warmer temperatures for germination and growth. Any temperature below 10°C can lead to the plant's death. If grown indoors, the plant requires an average temperature of 22-26°C.
Soil Requirements
The Phaseolus lunatus L. plant requires well-draining soil with a pH range of 6.0-6.8. It prefers soil that is rich in organic matter and nutrients. The soil must be loamy and sandy, with a silt content not exceeding 35%. The plant also requires adequate moisture for healthy growth, but the soil must not be waterlogged. A regular supply of compost and manure can help improve soil quality and enhance plant growth.
Cultivation methods
Phaseolus lunatus L. or lima bean is an annual plant that thrives well in warm and humid environments. It grows best in well-drained loam soil that is rich in organic matter. The plant prefers a pH range of 6.0 to 6.5 for better growth and productivity. It is recommended to plant the seeds directly in the soil when the temperature reaches at least 15°C and the risk of frost has passed. Lima beans require a moderate amount of sunlight and should be protected from harsh winds by planting them near a fence or other windbreakers.
Watering needs
Lima beans require consistent watering, especially during the flowering and pod formation stages. It is recommended to water the plants once or twice a week with 1 inch of water. During prolonged dry periods, consider increasing the frequency of watering to keep the soil moist. Overwatering can lead to root rot and other fungal diseases. Avoid wetting the leaves and flowers while watering the plants as it may encourage the development of fungal diseases.
Fertilization
Liming the soil to maintain the pH level is an important step to ensure nutrient availability for the plant. Lima beans require moderate amounts of nitrogen for vegetative growth and phosphorus and potassium for flowering and fruiting stages. To achieve optimum yield, consider applying a balanced fertilizer at the time of planting, and then side-dress the plants with nitrogen-rich fertilizers during the vegetative stage and phosphorus and potassium-rich fertilizers during the flowering stage.
Pruning
Pruning is not typically required in lima beans. However, occasionally removing the lower leaves helps increase airflow around the plant's base, reducing the risk of fungal diseases. Additionally, removing the dried up or diseased leaves, pods, and vines can help reduce the spread of fungal diseases to other parts of the plant. It is recommended to carry out pruning activities during the dry weather as the wet weather can facilitate the spread of disease.
Propagation of Phaseolus lunatus L.
Phaseolus lunatus L., commonly known as lima bean or butter bean, is a warm-season crop that is widely cultivated for its edible seeds. It is an annual plant that belongs to the Fabaceae family, and it is native to Central and South America.
Seed Propagation
Seed propagation is the most common method of growing Phaseolus lunatus L. The seeds are directly sown into the soil after the danger of frost has passed and the soil has warmed up to at least 60°F. The seeds should be planted one inch deep and four to six inches apart in rows that are two to three feet apart. Lima beans have a high germination rate, and the seedlings emerge within a week or two.
Before planting, it is advisable to soak the seeds in water overnight to speed up the germination process. It is also recommended to inoculate the seeds with rhizobia bacteria to help fix nitrogen in the soil. This can be done by dusting the seeds with inoculant powder just before planting.
Transplanting
Phaseolus lunatus L. can also be propagated by transplanting. This method involves starting the seeds indoors three to four weeks before the last expected frost date. The seeds should be sown in individual pots filled with seed starting mix. After germination, the seedlings should be placed in a bright location with temperatures between 60°F and 70°F and ample ventilation.
When the seedlings have developed a strong root system and are four to six inches tall, they can be transplanted outdoors. The seedlings should be planted in rows two to three feet apart and spaced four to six inches apart within the rows.
Cuttings
Propagation of Phaseolus lunatus L. by stem cuttings is possible, but not commonly practiced. It involves taking a three to four-inch cutting from a healthy, disease-free plant and planting it in a soilless mix or a mixture of perlite and vermiculite. The cutting should be kept in a warm, humid environment with bright, indirect light until it roots. Once roots have developed, the cutting can be transplanted to a garden bed.
In conclusion, Phaseolus lunatus L. can be propagated by seed, transplanting, and stem cuttings. Seed propagation is the most common and efficient method of growing lima beans.
Disease and pest management of Phaseolus lunatus L.
Phaseolus lunatus L., commonly known as Lima bean, is a legume crop that is widely cultivated around the world. While this crop is known for its high nutritional value and yield potential, it is also susceptible to several pests and diseases that can cause significant damage to the crop.
Diseases
The most common diseases that affect Phaseolus lunatus L. are:
- Anthracnose: a fungal disease that causes dieback, leaf spots, and pod rot. To manage this disease, crop rotation, use of resistant cultivars, and fungicides are recommended.
- Bacterial wilt: a bacterial infection that causes wilting, stunting, and yellowing of the plant. This disease can be managed by using disease-free seeds, crop rotation, and sanitation practices.
- Fusarium wilt: a fungal disease that causes yellowing, wilting, and eventual death of the plant. To manage this disease, crop rotation, use of resistant cultivars, and fungicides are recommended.
Pests
The most common pests that affect Phaseolus lunatus L. are:
- Aphids: small insects that suck the sap from the plant, causing stunted growth and deformation. To manage this pest, the use of natural enemies, insecticidal soaps, and oil sprays are recommended.
- Cutworms: larvae of moths that cut through the stem of the seedlings. To manage this pest, the use of physical barriers, such as cardboard collars, and biological controls, such as beneficial nematodes, are recommended.
- Spider mites: tiny insects that causes yellowing, stunted growth, and leaf drop. To manage this pest, the use of natural enemies, such as predatory mites, and insecticidal soaps are recommended.
Overall, it is essential to monitor the crop and identify problems early to manage diseases and pests effectively. Integrated pest management strategies, such as cultural, biological, and chemical control methods, should be used to manage these problems sustainably.
