Split peas are the dried, mature seeds of the field pea, typically a variety of Pisum sativum var. arvense. Unlike sweet garden peas eaten fresh, these plants are cultivated specifically for their nutrient-dense, storable seed. They are a hardy, cool-season legume, making them a popular choice for cover cropping or a dry staple crop in the home garden.
Essential Planting Requirements
Field peas are a cool-season crop, so planting should occur very early in the spring, often four to six weeks before the last expected frost date. They can handle soil temperatures as low as 40°F for germination, and established plants tolerate heavy frost. In areas with mild winters, a second crop can be planted in late summer or early fall for a winter harvest.
The planting location requires full sun exposure throughout the growing season to maximize pod set and ensure complete drying. Peas prefer well-drained soil and will not tolerate standing water or saline conditions, which can quickly lead to rot. An ideal soil pH is near neutral (around 7.0), but they are adaptable to a range from slightly acidic to slightly alkaline.
As legumes, peas benefit significantly from a specific inoculant containing Rhizobium leguminosarum bacteria, which helps the plant fix atmospheric nitrogen. Applying this powder to the seeds immediately before sowing encourages nodule formation on the roots, reducing the need for external nitrogen fertilizer. Seeds should be sown about 2 inches deep and 2 inches apart to ensure optimal plant density.
Tending the Growing Plants
Field peas, especially vining varieties grown for dry seed, require vertical support as they mature. Utilizing trellises, netting, or planting them alongside tall crops like corn gives the plants’ tendrils a structure to climb. This practice prevents the vines from lodging (falling over), which keeps developing pods off the damp ground and reduces the risk of fungal diseases.
Consistent moisture is important early in the plant’s life to support vigorous foliage and flower production. Once the pods begin to swell and mature, the watering regimen should be significantly reduced. Less water encourages the plant to direct energy into drying down the seeds, which is necessary for a dry pea harvest.
Gardeners should monitor for common pea ailments like powdery mildew, which appears as a white, dusty growth on leaves and stems. It often appears later in the season when temperatures rise and air circulation is poor, and can be managed with organic fungicide sprays. Aphids are another common pest, but a strong blast of water or the introduction of beneficial insects often keeps their populations in check.
Harvesting Dry Peas
The objective for dry pea harvest is to allow the entire plant to senesce, or dry out, naturally in the field, concentrating energy into the seed. This stage is reached when the vines have turned fully yellow and brown, and the pods are brittle, often 90 to 105 days after planting.
A good indicator of readiness is when the bottom pods are fully ripe, the middle pods are yellow, and the uppermost pods are beginning to turn yellow. At this point, the entire vine should be cut at the base using pruners or a scythe, rather than pulling the plants out of the ground. This minimizes soil disturbance and root damage.
The cut vines must then be moved to a dry, protected location for a final curing period. Spreading the vines on a tarp or hanging them in a well-ventilated barn or shed for one to two weeks ensures that all residual moisture evaporates. This curing step is important because dry peas stored with too much moisture content will quickly mold or spoil.
Preparing the Split Peas
After the vines are fully cured, the dried peas must be removed from their brittle pods through threshing. For the home gardener, this can be accomplished by placing the dried vines in a large bag or on a tarp and walking or lightly stomping on them to break open the pods. The resulting mixture of peas, pod fragments, and leaves is called chaff.
The next step is winnowing, which separates the heavy dried peas from the lighter chaff and debris. Pouring the mixture slowly between two containers on a breezy day allows the wind to carry away the lighter material. The whole dried peas should then be spread out and inspected manually to remove any small stones, dirt clumps, or damaged seeds.
What is a Split Pea?
The term “split peas” refers to the final product where the seed coat, or hull, is removed, causing the pea’s two cotyledons to separate along their natural seam. While commercial operations use specialized dehulling equipment, the home gardener’s yield is the whole dried pea. These whole peas can be cooked as is or will often split naturally during cooking.
The final, cleaned whole dried peas should be stored in an airtight container in a cool, dark, and dry place to prevent the growth of mold or weevil infestation.