Phaseolus lunatus: complete guide

Overview

Phaseolus lunatus, commonly called Lima Bean, is an annual climbing plant from the Fabaceae family. This bean naturally occurs from Mexico through Colombia. The plant is prized for its large, nutritious seeds that can be fully ripened. Lima beans are protein-rich and nourishing, with a soft, buttery flavor. The plant grows quickly and produces abundantly during the growing season.

Appearance and bloom

Phaseolus lunatus reaches heights of 150 to 250 centimeters when vertically supported. The plant has large, compound leaves with three leaflets. The flowers are small, white to yellow or violet, growing in dense clusters. The pods are flat, roughly 7 to 10 centimeters long and contain two to four large, flat seeds. These seeds have a characteristic moon or kidney shape, hence the name lima bean.

Ideal location

Phaseolus lunatus thrives in full sun. The plant needs 6 to 8 hours of direct sunlight daily. Place the plant against a south-facing wall or pergola. The plant benefits from warm conditions and grows better in warm climate. In temperate regions, sow early for sufficient growing period. Protect against cold wind.

Soil

Phaseolus lunatus prefers well-draining, fertile soil. The ideal pH range is 6.0 to 7.5. Work compost or animal manure in before sowing for better growth. The plant grows in virtually all soil types but prefers light, well-worked soil. Heavy clay soils must be improved with sand or compost.

Watering

Phaseolus lunatus has moderate moisture needs. Water regularly, especially during drought. The plant prefers constant moisture without waterlogging. Water at plant base, not on foliage, to prevent fungi. During bloom and pod-setting periods, water is essential. In very dry summers, daily watering may be necessary.

Maintenance

Phaseolus lunatus requires vertical support. Place a stake, strings or trellis near the plant before it grows too large. Train the plant to grow along the support. Remove dead or injured leaves. The plant may benefit from phosphate-rich fertilizer for better seed production. Sow seeds directly in ground after all frost danger.

Maintenance calendar

May: Sow seeds after all frost danger. June: Plant establishes and begins growing. July to August: Bloom and pod formation. September to October: Seed maturation. October to November: Harvest ripe pods and seeds.

Winter hardiness

Phaseolus lunatus is not winter hardy. It is an annual that dies at frost temperatures. In warm regions it may overwinter, but in temperate zones it dies in fall. The plant must be resown annually.

Companion plants

Phaseolus lunatus grows well as a companion plant in vegetable gardens. Plant it with corn and squash as part of the traditional Three Sisters polyculture. The plant also combines well with tomatoes and basil. Avoid fennel as a plant neighbor.

Closing thoughts

Phaseolus lunatus is a valuable vegetable for temperate gardens, if well-planned. The plant benefits from warm soil and sufficient growing period. Harvesting fresh lima beans is highly rewarding. The seeds can also be dried and stored for winter cooking. Plant lima beans this season in a warm corner of your garden. Discover more ways to grow vegetables on gardenworld.app. Let gardenworld.app help you plan a productive vegetable garden with optimal plant placements today.