Vegetable · Fabaceae
Field Pea
Pisum sativum subsp. arvense
Sow it with a grain to climb, and the field pea builds your soil and feeds it nitrogen for free.
Full sun
Every 5–10 days
60–90 days
USDA 6–8
Overview
Field pea is the workhorse cousin of the garden pea, the very same species grown for its vines instead of its sweet pods. It belongs to the legume family and traces back to the old grain fields of Europe and the Near East. Gardeners and farmers grow it as a cover crop and green manure, where it builds the soil rather than fills the dinner plate, though its young shoots and peas are still good to eat.
The big draw is what it does underground. Like other legumes, it teams up with soil bacteria to pull nitrogen out of the air and fix it into the ground, leaving the bed richer than it found it. Mow or till the crop in at full bloom and the next planting feeds on that stored nitrogen.
The vines are long, soft, and weak, so a stand left on its own flops over and mats down. That's why field pea is almost always sown with a small-grain nurse crop like oats or rye for the tendrils to climb. Match the type to your winters, give it cool weather and steady water, and it does the rest.
Care
The short version: full sun and cool weather, steady moisture since it hates heat and drought, well-drained soil of moderate fertility, and a small-grain nurse crop to climb on. Inoculate the seed and skip the nitrogen, because the plant makes its own.
Light
Field pea wants full sun, though it takes a little partial shade. As a cool-season crop it cares more about temperature than sheer light, so it does best when the days are bright but the weather stays cool.
Water
Keep the soil evenly moist, since this is a cool-season legume with shallow drought tolerance. It dislikes heat most of all, and once temperatures climb past 90°F (32°C) the flowers blast and seed yield drops. Steady moisture through cool weather is what carries the crop.
Soil
It grows on well-drained clay or heavy loam of moderate fertility and does fine on loamy sands too. Aim for a pH between 6.0 and 7.5. The one rule that matters is drainage, because soggy ground invites the root rots that plague peas.
Temperature
This is a cold-tolerant cool-season crop, and the hardy winter types handle down to about 10°F (-12°C) with only minor injury. The trouble is at the top end, where anything above 90°F (32°C) blasts the flowers and cuts the seed set.
Humidity
Ordinary outdoor humidity suits it, so there's no number to chase. Airflow and drainage matter far more, since damp, crowded growth is what brings on mildew and the leaf and stem blights.
Feeding
Here's where field pea earns its keep: as a nitrogen-fixing legume it needs little to no nitrogen fertilizer. Inoculate the seed with Rhizobium at planting so the nodules form, and add phosphorus or potassium only if a soil test comes back low.
Pruning
There's no pruning to do. Instead, the whole crop is terminated at or before full bloom, mowed, tilled, rolled, or left to winterkill, which is when it holds the most nitrogen for the soil.
Repotting
none
Size & spacing
12–47 in (30–120 cm) tall
When to plant
Field pea runs on cool weather and has no use for summer heat. In mild zones, sow Austrian winter pea from mid-August into September so it overwinters, and in colder areas wait and sow spring field peas as soon as the ground can be worked. Either way, the flowers open in spring, and that's the cue to terminate the crop for the most nitrogen.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Not started indoors; direct-sown in the field
- Plant: Sow Austrian winter pea from mid-August to mid-September to overwinter in mild zones (roughly USDA 6-8); sow spring field peas as early as the soil can be worked in colder areas
- Harvest: Pink-and-purple to white pea flowers in spring; terminate at or before full bloom for maximum nitrogen
Hardiness
USDA hardiness zones: 6–8
Temperature: down to -23°C
Troubleshooting
Most field pea trouble traces back to three things: vines with nothing to climb, winters too hard for the type you sowed, and soil worn out by tight rotations. Read the early signs below and match what you see, then act while it still does some good.
Vines flop over and rot on the ground
Field pea stems are long and soft, so a stand grown on its own tends to lodge and mat down where the bottom growth turns yellow and rots. Sow the peas with a small-grain nurse crop such as oats, rye, or barley for the tendrils to grab. Drop the pea seeding rate by about a quarter and the grain by about a third, and the planting stays upright.
Fix:
- Grow the peas with a small-grain nurse crop such as oats, rye, wheat, barley, or triticale for the tendrils to climb
- Reduce the pea seeding rate by about one quarter and the grain by about one third in the mix
Winter pea browns and collapses after a hard freeze
This is winterkill, and it hits Austrian winter pea grown colder than its range or sown too late to bulk up. The hardy types shrug off about 10°F (-12°C) with minor injury, but sustained cold near 18°F (-8°C) without snow cover finishes them. In cold zones, lean into it and use the dead vines as a winter-killed mulch, or switch to spring-sown field peas instead.
Fix:
- In cold zones treat winterkill as a feature and use it as a winter-killed mulch, or switch to spring-sown field peas
- Choose winter-hardy cultivars and plant early enough to reach 6 to 8 inches tall before soil freezes
Patchy, pale plants with no root nodules
When the seed goes into ground that hasn't grown peas for years, the right Rhizobium may not be there, so few nitrogen-fixing nodules form and the plants stay yellow-green and weak. Dig a few roots and check for pink, active nodules to confirm it. Re-inoculate with fresh inoculant right before seeding and sow again.
Fix:
- Re-inoculate and re-seed with fresh, viable Rhizobium inoculant applied immediately before seeding
Yellowing, wilt, rots, leaf spots, or white powder
A spread of diseases hits peas in tight rotations and wet soil, from Sclerotinia and root rots to Ascochyta blight and powdery mildew, and pea aphids feed on the shoots while spreading viruses. Browned, rotted roots point to root rot, dark stem and leaf lesions to Ascochyta, and white fuzz to mildew. Rotate out of peas for several years, plant on well-drained ground, and reach for resistant cultivars and clean, treated seed.
Fix:
- Rotate out of peas for several years and avoid wet, poorly drained ground
- Use resistant or tolerant cultivars and clean, treated seed
- Scout for pea aphids and manage where thresholds are reached
Toxicity
Good news here, since field pea is the same species as the garden pea and carries no toxins. The shoots, pods, and peas are safe food for people and pets, and the vines make solid forage. The only thing to watch is heavy grazing of lush growth in cattle, sheep, and goats, which can cause bloat rather than any poisoning.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Peas are safe around cats, and a curious nibble of a shoot won't poison one. Most cats simply aren't interested in the foliage.
Dogs None
There's nothing in a field pea that harms a dog. Cooked peas even turn up in plenty of pet foods as a wholesome ingredient.
Horses Safe
Horses can graze the vines without trouble, and the crop is grown as forage for good reason. Introduce any rich new pasture gradually, as you would with any lush green feed.
Rabbits Safe
The tender shoots and leaves make fine rabbit food. Offer them alongside hay rather than as the whole meal.
Livestock Mild
Cattle, sheep, and goats thrive on pea forage, with one caveat: grazing heavy, lush growth can bring on bloat, a digestive gas buildup rather than poisoning. Ease animals onto the stand and pair it with grass to keep things settled.
Birds Safe
Chickens and other backyard birds happily eat the peas and greens. Both wild and farmed birds treat the seed as a welcome food.
People Safe
This is the same species as the garden pea, so the young pods, peas, and shoots are good to eat. Pick them tender for the best flavor.
Immature pods, peas, and tender shoots are edible. Like other legumes, lush pea forage can cause bloat in ruminant livestock if grazed heavily, but it is not poisonous to pets or people.
Varieties
Field peas come as fall winter types and spring types, and the right one depends mostly on how cold your winters run. These are the ones you'll see most.
Austrian Winter Pea
A cold-hardy fall type with bicolored purple and pink flowers and small, dark speckled seeds, sown in late summer to overwinter in mild zones.
Whistler
A winter-type forage and cover-crop field pea bred for cold-hardy fall planting.
40-10
A widely grown winter forage line used as a cover crop and green manure.
Spring forage field peas
Spring-sown types for colder regions where a fall-sown winter pea would simply winterkill.
Companions
Field pea grows best beside the small grains that hold its weak vines up, which is why nearly every cover-crop mix pairs the two.
Plant near
Oats: A small-grain nurse crop gives the weak pea vines something to climb on and adds biomass, reducing lodging.
Cereal rye: Provides upright support for the climbing tendrils and pairs well in fall-sown cover-crop mixes.
Barley: Serves as a nurse grain that supports the vines and balances the pea's nitrogen with a carbon-rich companion.
How to propagate
Field pea grows from seed and nothing else, sown straight into the ground rather than started in pots. The trick is less about the sowing and more about pairing the seed with the right inoculant and a grain to lean on.
SeedEasy
Fall (mid-August to mid-September) for Austrian winter pea in mild zones; early spring for field peas in colder areas · Emerges in about 1-2 weeks; reaches usable size within several weeks to a couple of months
Field peas are direct-sown from seed, never started indoors. In mild zones, sow Austrian winter pea from mid-August to mid-September; in colder areas, sow field peas as early as the soil can be worked in spring. Coat the seed with the right Rhizobium inoculant right before planting and sow it with a small-grain nurse crop for support. Seedlings break ground in about 1 to 2 weeks and reach usable size within several weeks to a couple of months.
Myths
The field pea is a different plant from the edible garden pea.
They are the same species, Pisum sativum. The field pea is just the forage subspecies arvense, picked for vigorous vining cover-crop growth rather than sweet shelling. Its tender shoots and peas are perfectly edible, the plant is simply grown for soil-building and forage.