Vegetable · Fabaceae
Green Bean
Phaseolus vulgaris
Drop the seed in warm soil and you'll be picking green beans 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 easiest crops to get right, which makes them perfect if you're just starting out. They're part of the legume family and go way back to the Americas, where folks have grown them for thousands of years. Pop the seed into warm soil and you'll get a fast, generous plant that hardly asks for anything in return.
So which kind should you grow? It really comes down to habit. Bush beans stay short and tidy and give you most of their crop in one quick wave, which is handy for a small bed or a few staggered sowings. Pole beans climb for weeks and just keep handing over pods all summer, as long as you give them something to grab onto.
Here's what's cool about beans: they basically feed themselves. Their roots buddy up with soil bacteria to grab nitrogen right out of the air, so they'll happily grow in poor ground that would starve other crops. Keep them watered while they flower, pick the pods young, and they'll keep giving for weeks.
Care
The short version: full sun, warm soil, and steady moisture once the flowers show up. Sow the seed right where it'll grow, go easy on the fertilizer, and pick the pods young and often so more keep coming.
Light
Beans want full sun, so aim for at least six to eight hours of direct light a day. Give them the brightest spot you've got, because shade just gets you leggy plants and a thin, late crop.
Water
Give them about 1 inch (2.5 cm) of water a week and keep the soil evenly moist, especially while they're flowering and setting pods. Water at the base and keep it off the leaves, since wet foliage is basically an invitation for rust and other diseases.
Soil
Go with well-drained loam that's got plenty of organic matter mixed in. A pH of 6.0 to 6.8 works nicely, just a touch acidic, and loose ground that drains well keeps the seed from rotting before it can sprout.
Temperature
Beans are happiest between 61°F and 84°F (16°C to 29°C). They need warm soil to sprout, and a late frost will finish off young plants, so there's really no point rushing them outside.
Humidity
Regular outdoor humidity is totally fine, so there's no number to chase. Airflow matters way more than the humidity itself, since crowded, damp leaves are exactly how rust and other fungal stuff gets going.
Feeding
Beans make their own nitrogen, so they barely need anything. A light dose of balanced fertilizer at planting does the job, and going heavy just grows leaves instead of pods.
Pruning
There's no real pruning to do here. Just pinch off any diseased leaves you notice, and pick the pods often, because a regular harvest keeps the plant making more.
Size & spacing
Plants run anywhere from 1 to 10 feet (30 cm to 3 m) tall, depending on whether you go bush or pole. A spread of 8 to 18 inches (20 to 46 cm) means each one needs a little space so air can move and disease stays away.
When to plant
Green beans love warmth and can't handle frost at all, so don't jump the gun. Wait until the last frost is done and the soil has warmed up, then sow the seed straight into the garden. Pick the tender pods every few days through summer and the plants just keep going.
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 problems turn up on the leaves or the pods, and honestly, a quick look usually tells you what's up. Find what matches below, then deal with it while it's still small. Catching it early is what keeps a little setback from spreading down the whole row.
Leaves chewed to lace with larvae hiding below
Leaves gone lacy? That's usually the Mexican bean beetle, and its copper adults and spiny yellow larvae munch the soft bits between the veins until the leaf looks like netting. Flip a few leaves over and you'll spot the larvae and yellow eggs tucked underneath. Pick off the adults, larvae, and egg masses by hand, and once you've harvested, clear out the old plants so nothing hangs around to come back next year.
Fix:
- Handpick adults, larvae, and egg masses
- Apply approved insecticide if infestation is heavy
Rusty spots on leaves that yellow and fall off
See raised rusty bumps that leave a powdery smudge on your fingers? That's bean rust, a fungus, and a heavy case turns leaves yellow and drops them early. Pull off the worst leaves so the fungus has less to work with. Then give plants some room to breathe and water down low at the base, because the trick is keeping the leaves dry.
Fix:
- Remove and destroy infected foliage
- Apply a labeled fungicide if severe
Flowers falling off without making pods
When it gets hot, past about 85°F to 90°F (29°C to 32°C) while the plants are blooming, the flowers just let go and you get no pods. Don't go hunting for a bug, though, because this is plain heat stress. Keep the soil evenly watered and wait it out, and the plants will get right back to setting pods once things cool off.
Fix:
- Maintain even soil moisture
- Wait for cooler temperatures to resume pod set
Dark sunken spots forming on the pods
Round sunken spots with dark edges, maybe with a bit of pink ooze, usually mean anthracnose. It tends to ride in on infected seed and then spreads fast whenever you brush past wet plants. So pull and toss the affected plants and pods, don't save their seed, and just start clean next season with healthy seed in a fresh spot.
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 won't poison you or your pets, so you can relax. The tender snap pods are good raw or cooked, and cooked beans are a common treat for dogs. The one thing to remember? 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
Cats are fine around green beans. If yours nibbles a leaf or a tender pod, there's nothing in the plant to worry about.
Dogs None
Dogs are totally fine here, and plain cooked pods are actually a favorite low-calorie treat that lots of owners hand out.
Horses Safe
Horses have nothing to fear from bean plants, since neither the leaves nor the pods carry anything that would hurt them.
Rabbits Safe
Rabbits can safely graze the leaves and young pods, though like any fresh green, it's best to keep the helpings small.
Livestock Safe
Cattle, goats, and sheep can browse a bean patch without getting poisoned, so the growing crop isn't a worry.
Birds Safe
Backyard hens and other birds can peck at the leaves and tender pods and be perfectly fine.
People Safe
Tender snap pods are great raw or cooked, no problem at all. It's only the mature dry seeds that 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
There are hundreds of bean varieties out there, but a few reliable names show up in most gardens. Here are the ones worth knowing before you grab a packet.
Blue Lake
A big-cropping favorite you'll find as both a bush and a pole bean, loved for round, tender pods that snap clean and don't have strings.
Kentucky Wonder
A tough old pole bean that gardeners keep growing for its full-flavored, meaty pods.
Provider
An early bush bean that doesn't mind cool soil, so it's a smart pick when you want to get the first planting in.
Contender
An early bush snap bean with stringless pods that holds up well against the usual bean 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 it gets. You grow them from seed sown right where they'll live, since they'd really rather not be 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
Just pop the seed right into the garden once the frost's gone and the soil has warmed to at least 60°F (16°C). Beans don't like their roots messed with, so there's no reason to bother with transplants, and don't rush them into cold, wet ground or they'll rot instead of sprout. Give them warm soil and you'll see seedlings in about 7 to 14 days.
Myths
Green beans have to be soaked or cooked before you eat them, just like dry beans.
That whole soak-and-cook thing is really about mature dry seeds, which carry lectins that only heat can break down. But tender young snap pods are fine raw or lightly cooked, so the warning you hear about beans just doesn't apply to the green pods you pull off the vine.
Beans need a big hit of nitrogen fertilizer to crop well.
Here's the thing: beans team up with rhizobia bacteria in their roots and make their own nitrogen from the air. Give them extra and you just get a bushy, leafy plant with hardly any pods, so a light feed at planting is really all they want.