Vegetable · Fabaceae
Green Bean
Phaseolus vulgaris
Sow them straight in warm soil and green beans give you pods by the handful all summer.
Full sun
Every 2–7 days
61–84°F · 16–29°C
50–65 days
Overview
Green beans are one of the friendliest crops a beginner can grow. They belong to the legume family and trace back to the Americas, where people have grown them for thousands of years. Drop the seed in warm soil and you get a fast, generous plant that asks for very little in return.
The choice comes down to habit. Bush beans stay low and compact and ripen most of their crop in a short burst, which suits a small bed or a quick succession of plantings. Pole beans climb for weeks on end and keep handing you pods right through summer, as long as you give them something to scramble up.
What makes beans special is that they feed themselves. Their roots partner with soil bacteria to pull nitrogen straight from the air, so they shrug off poor ground that would starve other crops. Keep them watered through flowering, pick the pods young, and the plants reward you for weeks.
Care
The short version: full sun, warm soil, and steady moisture once the flowers open. Sow the seed where it will grow, go light on fertilizer, and pick the pods young and often to keep more coming.
Light
Beans want full sun, with at least six to eight hours of direct light a day. Plant them in the brightest spot you have, because shade gives you leggy plants and a thin, late crop.
Water
Give about 1 inch (2.5 cm) of water a week and keep the soil evenly moist, most of all while the plants are flowering and setting pods. Water at the base and keep it off the leaves, since wet foliage invites rust and other diseases.
Soil
Plant in well-drained loam with plenty of organic matter worked in. A pH of 6.0 to 6.8 suits them, slightly on the acidic side, and loose ground that drains well keeps the seed from rotting before it sprouts.
Temperature
Beans do best between 61°F and 84°F (16°C to 29°C). They need warm soil to germinate, and a late frost will kill young plants, so there's no point rushing them out early.
Humidity
Ordinary outdoor humidity is fine, so there's no number to aim for. Airflow matters far more than the level itself, since crowded, damp leaves are how rust and other fungal problems take hold.
Feeding
Beans fix their own nitrogen, so they need almost nothing. A light dose of balanced fertilizer at planting is plenty, and a heavy hand only grows leaves at the expense of pods.
Pruning
There's no routine pruning to do. Just pinch off any diseased leaves you spot, and pick the pods often, since regular harvest keeps the plant setting more.
Size & spacing
Plants run from 1 to 10 feet (30 cm to 3 m) tall depending on whether you grow bush or pole types. Spread of 8 to 18 inches (20 to 46 cm) means each plant needs a little elbow room so air can move and disease stays down.
When to plant
Green beans are warm-season plants with no tolerance for frost. Wait until the last frost has passed and the soil has warmed, then sow the seed straight into the garden. Pick tender pods through summer, every few days, and the plants keep producing.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: After last spring frost when soil has warmed to at least 60°F
- Harvest: Harvest immature tender pods through summer, picking every few days
Hardiness
USDA hardiness zones: 2–11
Temperature: down to -46°C
Troubleshooting
Most bean trouble shows up on the leaves or the pods, and a quick look usually tells you what's going on. Match what you see below, then act while the problem is still small. Catching it early is what keeps a setback from spreading down the row.
Lacy, skeletonized leaves with spiny larvae underneath
This is the Mexican bean beetle, whose copper adults and spiny yellow larvae chew the soft tissue between leaf veins until the foliage looks like lace. Check the undersides, where the larvae and yellow egg clusters hide. Pick off every adult, larva, and egg mass you find, and clear out the spent crop after harvest so the beetles have nowhere to settle next year.
Fix:
- Handpick adults, larvae, and egg masses
- Apply approved insecticide if infestation is heavy
Rusty pustules on the leaves with yellowing and leaf drop
Those raised, rusty bumps are bean rust, a fungus that powders your fingers with spores when you rub a leaf. Bad cases yellow the foliage and strip it early. Strip off the worst leaves, give plants room so the air can dry them, and water at the base rather than over the top.
Fix:
- Remove and destroy infected foliage
- Apply a labeled fungicide if severe
Flowers fall off without setting any pods
When the heat climbs past roughly 85°F to 90°F (29°C to 32°C) during bloom, beans abort their flowers and set nothing. It is heat stress, not a pest or disease. Keep the soil evenly watered and the plants will start setting pods again on their own once the weather cools.
Fix:
- Maintain even soil moisture
- Wait for cooler temperatures to resume pod set
Dark, sunken spots on the pods
Circular sunken lesions with dark rims, sometimes oozing pink spore masses, point to anthracnose. The fungus rides in on infected seed and spreads fast when you brush past wet plants. Pull and bin any affected plants and pods, never save seed from them, and start clean next year with disease-free seed and a fresh patch of ground.
Fix:
- Remove and destroy infected plants and pods
- Do not save seed from infected plants
Toxicity
Green beans are a safe, edible crop, and the growing plant poses no poison risk to people or pets. The tender snap pods are good to eat raw or cooked, and cooked beans are a common treat for dogs. The only thing to keep in mind is that mature dry seeds need cooking before anyone eats them, since raw dried beans hold lectins.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Green beans are safe around cats. A cat that nibbles a leaf or a tender pod has nothing to fear from the plant.
Dogs None
Dogs can be near green beans without any worry, and plain cooked pods are a common low-calorie treat plenty of owners share.
Horses Safe
Horses are fine around bean plants. The foliage and pods carry no toxin that would harm them.
Rabbits Safe
Rabbits can graze the leaves and young pods safely, though as with any fresh green it is best offered in modest amounts.
Livestock Safe
Cattle, goats, and sheep can browse green bean plants without poisoning. There is no concern with the growing crop.
Birds Safe
Backyard hens and other birds can peck at the leaves and tender pods with no ill effect.
People Safe
Tender snap pods are a kitchen staple, eaten raw or cooked. Only the mature dry seeds need cooking first, since raw dried beans hold lectins.
Mature dry beans of Phaseolus contain lectins (phytohaemagglutinin) and should be cooked before eating, but tender immature snap pods eaten whole are not a pet-toxicity concern.
Varieties
Hundreds of bean varieties exist, but a few dependable names turn up in most gardens. These are the ones worth knowing before you pick a packet.
Blue Lake
A heavy-cropping favorite sold in both bush and pole forms, with round, tender pods that snap clean and string-free.
Kentucky Wonder
A vigorous old pole bean kept around for its full-flavored, meaty pods.
Provider
An early bush type that shrugs off cool soil, which makes it a good pick for the first planting of the year.
Contender
An early bush snap bean with stringless pods and solid resistance to common diseases.
Companions
Beans grow well with the crops that share their space without competing, and the three-sisters trio of corn, beans, and squash is the classic example. They sulk next to alliums like onions, which hold their growth back.
Plant near
Corn: Part of the traditional three-sisters planting; corn stalks provide support for climbing beans.
Squash: Three-sisters companion; squash foliage shades soil and suppresses weeds while beans add nitrogen.
Cucumbers: Cited as a compatible companion that grows well alongside beans.
Potatoes: Listed as a beneficial companion in extension companion-planting guidance.
Keep apart
Onions: Alliums such as onions and garlic are reported to inhibit the growth of beans.
How to propagate
Green beans are about as easy to start as a plant gets. You grow them from seed sown right where they will live, since they dislike being moved.
SeedEasy
Direct-sow after the last frost once soil reaches at least 60°F · Seedlings emerge in about 7-14 days under warm conditions
Sow the seed straight into the garden once frost has passed and the soil has warmed to at least 60°F (16°C). Beans hate having their roots disturbed, so skip the transplants, and don't rush them into cold, wet ground where they rot instead of sprout. In warm soil the seedlings push through in about 7 to 14 days.
Myths
Green beans must be soaked or cooked before eating, just like dry beans.
The soaking-and-cooking rule belongs to mature dry seeds, which hold lectins that need heat to break down. Tender immature snap pods are safe eaten raw or lightly cooked, so the warning you hear about beans simply doesn't apply to the green pods you pick off the vine.
Beans need a heavy dose of nitrogen fertilizer to crop well.
Beans partner with rhizobia bacteria in their roots and fix their own nitrogen from the air. Pile on more and you grow a lush, leafy plant with few pods to show for it, so a light feed at planting is all they want.