are green beans perennial

The Perennial Question Are Green Beans Actually Perennial Plants?

For many home gardeners green beans are a staple crop to plant each year. Their versatility and nutrients make them a favorite. But some may wonder – with proper care could green bean plants come back year after year, making them a perennial vegetable? Let’s explore the botany and growth habits of green beans to find out if they can be perennial plants.

What Makes a Plant Perennial?

Perennials are plants that live for multiple years, unlike annuals that complete their lifecycle in one season. Perennials emerge, grow, bloom, and go dormant over repeating cycles. Some key traits of perennials include:

• Cold hardy root structures that survive winter while above ground parts die back

• Re-sprouting from roots or crowns each spring.

• Maintenance of permanent structures like stems or branches year after year.

• Investment of resources into storage organs that enable re-growth.

Examples of common perennial garden plants are fruit trees, ornamental grasses, berries, asparagus, artichokes, and herbs like lavender or thyme.

Are Green Beans Annuals or Perennials?

Green beans (Phaseolus vulgaris) are actually tender annuals. Each season, the entire plant is grown from seed, produces pods and beans, then dies off completely at summer’s end as frosts arrive. Here’s an overview of their typical annual life cycle:

• Planted by seed in spring after danger of frost has passed.

• Quick-growing vines that produce leaves, flowers, then edible pods.

• Above ground vegetation dies back with first fall freeze.

• No structures remain alive through winter.

• Must be replanted anew next spring.

Unlike true perennials, green bean plants lack specialized overwintering root structures or food storage organs that would allow them to survive cold winters. Their shallow roots, stems, and foliage are not frost hardy. Once temperatures dip below freezing, the plants cannot tolerate the cold and will not re-emerge the following spring.

Why Don’t Green Beans Come Back Each Year?

Several key biological factors prevent green beans from being perennial plants:

• Tropical origins – native to warmer climates and unable to withstand frost.

• Lack of cold-hardy roots or food storage organs.

• Minimal energy invested into woody stems or permanent structures.

• Life cycle focused on quick seed production, not long-term survival.

• Thin roots close to soil surface are damaged by freezing and thawing.

• Vines and foliage killed by first hard fall frost.

Unlike related beans like scarlet runner beans, green beans were not bred for perennial traits. Attempts to overwinter them almost always end in failure. Once temperatures drop, the plants will quickly die without leaving any viable structures behind.

Getting Multiple Years from Green Beans

While individual green bean plants are not perennial, gardeners can still get multiple years of production through a few methods:

• Allow some pods to fully ripen and collect seeds for future planting. Avoid F1 hybrids.

• Practice crop rotation, allowing 3+ years between bean plantings in the same space.

• Amend soil fertility each season for sustained productivity.

• Choose resistant varieties and practice disease prevention to avoid soil-borne pathogens.

• Consider overwintering hardy legumes like fava beans to boost nitrogen for future bean crops.

• Use season extension techniques like cold frames or tunnels to add extra weeks of growth.

So while green beans themselves may not return each year, gardeners can certainly keep enjoying productive green bean patches season after season. Using sound horticultural practices, enriched soil, and saved seeds, you can experience years of abundant green bean harvests.

Growing Tips for Maximizing Green Bean Yields

Since green beans must be planted annually, here are some tips for getting the highest yields from each successive planting:

• Plant in loose, crumbly, fertile soil enriched with compost.

• Sow seeds directly in garden beds after danger of frost.

• Space rows 18-24 inches apart and seeds 2-4 inches apart within rows.

• Water soil regularly to maintain even moisture, especially during flowering and pod fill stages.

• Use trellises, frames, or fencing to support upright growth.

• Side dress with a balanced fertilizer when plants begin blooming.

• Protect from pests like bean beetles which can quickly defoliate plants.

• Harvest frequently, at least every 3-4 days, to encourage more pod production.

• Pull spent plants at end of season to disrupt disease and pest life cycles.

• Save seeds from particularly healthy, productive plants for future years.

With attentive care throughout the relatively short green bean growing season, you can enjoy yield after yield of snap beans, pole beans, or other preferred varieties.

The Perennial Potential in Some Bean Varieties

While standard green beans may not be perennial, gardeners shouldn’t dismiss beans entirely as only annuals. Some beans like runner beans, climbing beans, or fava beans can be overwintered in warmer climates, especially if protected from frost.

The key is selecting bean varieties bred specifically for perennial traits like:

• Tough, hardy root structures.

• Ability to go dormant and re-sprout.

• Resistance to rotting over winter.

• Propensity to self-sow.

• Adaptability to cool weather.

• Vigorous regrowth each spring.

So while green beans are decidedly tender annuals, nature offers some amazing perennial beans too. Expanding which beans you grow can let you enjoy their benefits year after year.

The Takeaway on Green Beans as Perennials

When it comes to green beans, don’t be fooled – their lifespan only lasts a single season. But armed with the right gardening practices and bean varieties, you can sustain plentiful harvests over many springs and summers to come. Though green beans themselves may not return each year, your enjoyment of their crisp flavor and bountiful yields certainly can!