Because snow peas Pisum sativum L. (Macrocarpon group) are at their crispiest, crunchiest best when freshly picked, they are a prime candidate for your early spring garden. Snow peas are a cold-season vegetable most commonly planted in the early spring, but they can also be planted in the late summer for fall harvest. In warm climates, some varieties can also be grown as a winter crop.
Both the pods and the peas are eaten, hence their name mangetout (which means all-eat in French). Fun fact: the flowers, and tendrils, or pea shoots, are also edible. Snow peas are a classic ingredient in stir-fries and salads.
|Common Name||Snow pea, mangetout, sugar pea, Chinese pea pods|
|Botanical Name||Pisum sativum L (Macrocarpon group)|
|Plant Type||Annual, vegetable|
|Size||36-72 in. vines|
|Sun Exposure||Full, partial|
|Soil Type||Loamy, moist, well-drained|
|Hardiness Zones||2a-11b (USDA)|
How to Plant Snow Peas
When to Plant
Snow peas, like other green peas, are an early spring crop that should be planted in the garden as soon as the soil can be worked, about four to six weeks before the average last frost date in your area. The ideal temperature for snow peas to germinate is between 45 and 70 degrees F. It is key that you take advantage of the short planting window because snow peas stop growing when temperatures hit 85 degrees F. If you enjoy the flowers and pea shoots, consider a consecutive planting just for the shoots, which can be harvested after only a few weeks.
You can also plant a fall crop about two months before the first average frost date. For fall planting, make sure to pick a variety that matures early and is resistant to powdery mildew, as the fungus is widespread in late summer.
Select a Planting Site
Choose a location in full sun to partial shade with well-draining soil. Follow crop rotation rules and don’t plant snow peas in the same spot where other legumes were planted in the last two years to reduce pests and diseases.
Spacing, Depth, and Support
Plant the seeds 1 1/2 to 2 inches apart and 1 inch deep. The space between the rows depends on how tall the vines grow. Varieties that are less than 3 feet tall can be spaced as little as 12 to 18 inches apart, while taller varieties should be spaced 18 to 36 inches apart. When spacing rows, keep in mind that you should have easy access for harvesting.
It is recommended to trellis snow peas regardless of the size of the vines to keep the vines upright towards the sunlight and off the ground where they can rot in wet weather. Peas are also much easier to pick on a trellis—even shorter varieties easily topple over under the weight of the pods.
A trellis net or chicken wire provides ample places for the pea tendrils to latch onto. The bottom of the trellis should be no more than 3 to 4 inches above the ground so the young plants can reach it quickly.
Snow Pea Plant Care
Snow peas grow in full sun, ideally with six to eight hours of direct sunlight, as well as in partial shade. Too much direct sunlight can scorch the tender vines.
The soil for snow peas should be well-drained and rich in organic matter, with a slightly acidic pH between 6.0 and 6.5.
Peas need ample water, at least 1 inch per week, or the pods can grow stringy and tough instead of crisp and crunchy. As the weather warms, keep late crops well-watered. Inadequate drainage can lead to seed and root rot.
Temperature and Humidity
Snow peas thrive in cool weather and can tolerate even occasional late snow flurries. Light frost in the spring or fall does not bother them, however, if the soil temperature is around 40 degrees F, germination takes longer. Like all peas, they do not perform well in temperatures above 85 degrees F. Humid weather is not a problem as long as the weather remains cool.
If the soil in your garden is rich in organic matter and has been amended with compost, fertilization of snow peas is usually not necessary.
Like all peas, snow peas are self-pollinating and don’t require insects or wind for pollination.
Types of Snow Peas
Snow pea varieties include:
- ‘Oregon Giant’: 60 to 70 days to maturity. At 30 to 36 inches, the vines of this variety are on the short side and resistant to fusarium wilt and powdery mildew. The pods are very large and sweet.
- ‘Oregon Sugar Pod’: 62 days to maturity. Vines of 36 to 43 inches produce stringless pods that come in pairs which means high yields and easy harvests. This variety is resistant to various diseases, including fusarium wilt and powdery mildew.
- ‘Avalanche’: 60 days to maturity. What makes this variety special is that the 36-inch vines produce lots of tendrils (pea shoots), which can be harvested. The abundance of tendrils also helps the plant support itself. The pods can be picked as baby or full-size pods. The variety is resistant to fusarium wilt and powdery mildew.
- ‘Mammoth Melting’: 70 days to maturity. With vines reaching 4 to 6 feet, this variety has large, sweet pods. It does well in freezing temperatures, which makes it a choice for a winter crop in zones 9 to 11.
Snow peas are harvested when you can feel the peas slightly enlarged inside the pods but before they form sizeable peas. The pods should still be flat. As the plants reach maturity, check them at least every other day as the pods grow fast. Harvest the snow peas frequently so the plant continues to produce.
Hold the vine with one hand and gently snap the pod from the plant with the other hand or use scissors to cut it off. Pea shoots should be harvested from the young plants as soon as they emerge. Pinch them off with your index finger and thumb or cut them off with garden snips. If you wait too long, the snow peas will become starchy and tough, and the pea shoots will become fibrous.
Growing in Pots
Plants will tall vines that need staking or trellising can be tricky to grow in containers because they are prone to toppling over. Fill a pot at least 12 inches in diameter with drainage holes with a combination of well-draining potting mix and compost and set up a trellis at planting time. Choose a dwarf variety and plant three or four seeds in the pot. Snow peas, like all container plants, need more frequent watering than garden plants.
Propagating Snow Peas
Snow peas are propagated from seeds. Most varieties are open-pollinated so you can collect the seeds for next year (for hybrid varieties, you need to purchase fresh seeds from a seed company). Leave a few pods on the plants and let the peas grow to full size and dry on the plant. When you can hear the peas rattle inside the pods, cut them off the vine and let them air dry for a few days, then store them in a cool and dry place until planting time.
How to Grow Snow Peas from Seed
While peas grow without inoculant, inoculating the pea seeds before planting is usually recommended, as it promotes the formation of nitrogen-producing nodules on the plant roots.
To plant the seeds:
- Till the soil to loosen it. Plant the peas 1 1/2 to 2 inches apart and 1 inch deep, in rows 12 to 36 inches apart. Water the soil evenly but gently with a nozzle or watering the seeds can rise. Keep the soil evenly moist.
- Snow pea seeds germinate in 5 to 10 days depending on the temperature.
Snow peas are an annual vegetable. Plants should be pulled and discarded after the harvest.
Common Pests & Plant Diseases
Snow peas can be affected by pea root rot, which manifests itself as yellowing and dieback of the foliage. Ways to prevent it is to follow crop rotation and make sure the soil is well-drained.
Powdery mildew, which usually appears in hot weather, is quite common in snow peas. Choose varieties that are resistant to powdery mildew.
Pest problems on snow peas include aphids and pea weevils. Sometimes it can be sufficient to wash them away with the garden hose fitted with a spray nozzle. If the infestation is more severe, spray the plants with insecticidal soap.
Are snow peas a vine or a bush?
Snow peas grow on delicate vines of varying lengths. Although dwarf varieties don’t grow taller than 3 feet, they should be supported with a trellis to make them grow upright.
Why do my pea seeds rise to the soil surface?
If the peas are planted too shallow, rain or watering can cause them to rise. Carefully push the seeds back into the soil as soon as possible (if they remain exposed, they will dry out and germination will stop) and gently tamp down the soil around them. To prevent the pea seeds from popping out of the soil, plant them 1 inch deep.
Do snow peas need thinning?
Generally, they don’t need thinning if planted correctly. Dense planting helps them support each other. But if the row is so dense that there is poor air circulation, you might want to remove a few plants to prevent the spread of disease. Always cut the extra seedlings at the soil line with scissors and never pull them out of the ground, to prevent damage to the roots of neighboring seedlings.
Peas: How to Grow. South Dakota State University Extension
Do I Need to Treat My Peas with an Inoculant Before Planting? Iowa State University Extension and Outreach.