Planting: Give early peas a sunny spot protected from high winds. Later crops may appreciate partial shade. You can also plant peas in mid to late summer for a fall crop. If possible, sow your fall crop in a spot where tall crops such as corn or pole beans will shade the young plants until the weather cools.
Early peas in particular like raised beds or a sandy loam soil that warms up quickly. Heavier soils, on the other hand, can provide cooler conditions for a late pea crop, but you'll need to loosen the ground before planting by working in some organic matter. Being legumes, peas supply their own nitrogen, so go easy on fertilizer. Too much nitrogen produces lush foliage but few peas.
Peas don't transplant well and are very hardy, so there's no reason to start them indoors. Pea plants can survive frosts but won't tolerate temperatures over 75°F. In fact, production slows down drastically at 70°F.
Southern gardeners often sow peas in mid to late fall so the seeds will lie dormant through winter and sprout as early as possible for spring harvest. On the West Coast and in Gulf states, you can grow peas as a winter crop. Elsewhere, if the spring growing season is relatively long and cool, plant your peas 4 to 6 weeks before the last frost, when the soil is at least 40°F. For a long harvest season, sow early, mid-season, and late cultivars at the same time, or make successive sowings of one kind at 10-day to 2-week intervals until the middle of May.
When planting peas in an area where legumes haven't grown before, it may help to treat seeds with an inoculant powder of bacteria, called Rhizobia. This treatment promotes the formation of root nodules, which contain beneficial bacteria that convert the nitrogen in the air into a form usable by plants. To use an inoculant, roll wet seeds in the powder immediately before planting.
Space seeds of bush, or dwarf, peas 1 inch apart in rows 2 feet apart. Bush peas are also good for growing in beds. Sow the seeds of early crops 2 inches deep in light soil or 1 inch deep in heavy soil; make later plantings an inch or two deeper. Thin to 2 to 3 inches apart. This close spacing will allow bush peas to entwine and prop each other up.
Plant vining types in double rows 6 to 8 inches apart on either side of 5- to 6-feet-tall supports made of wire or string, with 3 feet between each double row. The more simple the support, the easier it is to remove the vines at the end of the pea season and reuse it.
Generally speaking, 1 pound of seeds will plant a 100-foot row and should produce around 1 bushel of green peas or 2 bushels of edible pods. Another rough guideline is to raise 40 plants per person. Unused seed is good for 3 years.
To make good use of garden space, interplant peas with radishes, spinach, lettuce, or other early greens. Cucumbers and potatoes are good companion plants, but peas don't do well when planted near garlic or onions.
Growing guidelines: Providing peas with just the right amount of water is a little tricky. They should never be so waterlogged that the seeds and plants rot, and too much water before the plants flower will reduce yields. On the other hand, don't let the soil dry out when peas are germinating or blooming or when the pods are swelling. Once the plants are up, they only need about ½ inch of water every week until they start to bloom; at that time, increase their water supply to 1 inch a week until the pods fill out.
Peas growing in good soil need no additional fertilizer. If your soil is not very fertile, you may want to side-dress with compost when the seedlings are about 6 inches tall.
The vines are delicate, so handle them as little as possible. Gently hand pull any weeds near the plants to keep from damaging the pea roots. To reduce weeds and conserve moisture, lay 2 inches of organic mulch once the weather and soil warms. This also helps to keep the roots cool. Soil that becomes too warm can result in peas not setting fruit or can prevent already-formed pods from filling out. Mulch fall crops as soon as they are planted, and add another layer of mulch when the seedlings are 1 to 2 inches tall.
Once a vine quits producing, cut it off at ground level, leaving the nitrogen-rich root nodules in the ground to aid the growth of a following crop, such as brassicas, carrots, beets, or beans. Add the vines to your compost pile, unless they show obvious signs of disease or pest problems.