At PURIS, we partner with North American farmers to grow our yellow field peas and non-GMO soybeans, two versatile and high-value crops. While both are integral to sustainable agriculture and plant-based nutrition, they have distinct growing cycles, management needs, and benefits. Understanding these differences helps farmers optimize their operations for yield, soil health, and market demand.
Let's delve into the specifics of their growing cycle and what makes them different.
Yellow Field Peas Growing Cycle
The growing cycle of yellow field peas begins with planting seeds in early spring. These legumes thrive in cooler temperatures and are typically sown as soon as the soil can be worked, from mid-March to the first week of April. Their growing cycle can be broken down into these key stages:
Planting & Germination (Early Spring)
Yellow field peas can be sown into the grown early spring when soil can be worked and as low as 40-45°F. The germination process takes 10 to 14 days until emergence, during which a series of events occur, from water absorption to the development of the root that anchors the seed and the shoot that contains the stem and first leaves. Peas differ from soybeans as they go through "hypogeal germination," where the seed leaves remain underground while the shoot emerges. This protects the seed from early planting in case of late frost.
Emergence & Vegetative Growth (Late Spring - Early Summer)
After germination, peas develop quickly, with tendrils supporting upright growth and leaves forming to support photosynthesis. Yellow field peas are relatively low-input crops and a natural climate-smart crop compared to other crops. Peas can fix nitrogen through root nodules in the soil, a feature that comes with being a legume, and they leave excess nitrogen in the soil when they are done growing.
Photo - pea roots with nitrogen-fixing nodules from a PURIS farmer
Flowering and Pod Development (Mid-Summer)
Peas begin flowering about 40-50 days after planting (June or July), based on the growing degree days for pea growth. The flowers are self-pollinating, meaning they do not require insects or wind for fertilization. Once pollination occurs, pods form 7-10 days after flowering. The formation is mainly determinate, meaning most pea pods will mature simultaneously, allowing for uniform harvest.
Photo - Flowering and Pod Developing Pea Plant
Maturity and Harvest (Mid to Late Summer)
Peas typically mature 85-100 days after planting. Their leaves start yellow and drop, and the pods turn light tan to golden brown. The seeds harden and reach 12-16% moisture for harvest readiness. Depending on your maturity zone, double cropping may be possible.
Peas are typically harvested mid to late summer (July-August) and can be directly harvested through a combine. Harvest should occur before the peas have dried too much to prevent seed splitting or loss. Post-harvest, yellowfield peas fixate nitrogen in the soil, benefiting the next crop in rotation. Another bonus is less crop residue, allowing for no-till or reduced-till practices.
Photo - Field of peas being harvested with a combine.
Non-GMO Soybean Growing Cycle
Soybeans are a warm-season crop that requires higher soil temperatures. Planted later in the spring, they develop differently from peas in multiple ways.
Planting & Germination (Late Spring - Early Summer)
Soybeans are planted later than peas, as they favor warmer growing conditions, typically when the soil temperature reaches at least 55°F. The seeds germinate within 5-10 days, a little shorter than peas due to the warmer conditions. Compared to peas, soybean seed leaves emerge above the soil, known as "epigeal germination." This leaves them more susceptible to cold temperatures, hence why soybeans are planted a little later than yellow field peas.
Emergence & Vegetative Growth (Early to Mid-Summer)
After germination, the vegetative growth of soybeans develops extensive foliage, such as their trifoliolate leaves, which is crucial for photosynthesis and yield potential. Although soybeans are also a type of legume and can fix nitrogen, they require more nitrogen in their growing cycle.
Flowering and Pod Development (Mid to Late-Summer)
Soybean flowering is triggered by day length (photoperiod sensitivity) and occurs about 6-8 weeks after planting. Longer summer days speed up flowering, while shorter days slow it down. The flowers are also self-pollinating but are more influenced by external factors for successful fertilization. Pods form 10-14 days after flowering and are often indeterminate, meaning flowering and pod development continue for several weeks.
Maturity and Harvest (Early to Mid-Fall)
Soybeans have a more extended maturity period, usually 100-150 days from planting. Their leaves turn yellow then brown and their pods turn green to brown as their beans dry down to 13-15% moisture for optimal harvest.
Harvest starts late summer to fall (September-October) and is almost always harvested directly with a combine. Delayed harvest increases the risk of shattering (pods breaking open), especially in dry conditions. Soybeans leave a nitrogen credit that can reduce nitrogen use for the following crop. Soybeans also produce more crop residue, which can help prevent erosion but requires more management.
Key Differences
Both yellow field peas and soybeans serve as valuable crops for farmers, each offering unique advantages. Peas are an excellent choice for early planting, thrive in cooler conditions, and improve soil fertility through nitrogen fixation. Meanwhile, soybeans contribute to soil health with their robust residue cover and provide a versatile, high-demand crop for food and feed markets. Choosing between the two depends on climate conditions, market opportunities, and rotational benefits within a farming operation.
How to Tell a Pea Plant from a Soybean Plant
Are you unsure if you're looking at a pea or soybean plant? Here's a quick trick! Pea plants have delicate, vining tendrils that help them climb, and their leaves are smaller with a soft, feathery appearance. Soybean plants, on the other hand, are bushy with broader, oval-shaped leaves that grow in groups of three—earning them the nickname "trifoliate." So, if the plant looks ready to grab onto something, it’s a pea; if it’s standing firm and leafy, it’s a soybean!
PURIS - A pea and soybean company
PURIS is a leading force in the food production industry, specializing in cultivating and processing yellow field peas and non-GMO soybeans. With a commitment to sustainability and innovation, PURIS has become synonymous with high-quality, plant-based protein sources.
PURIS' focus on non-GMO farming practices and advanced agricultural techniques ensures its products meet and exceed industry standards. By investing in research and development, PURIS continues to drive the future of sustainable agriculture, providing farmers with the tools and knowledge needed to grow these essential crops efficiently and responsibly. We buy back from our contracted farmers the peas to manufacture our pea protein and starch in Dawson, MN, and the premium non-GMO soybeans to manufacturers that make tofu, natto, miso, and more.
Have questions or want to reach out to a PURIS growing expert? Contact us today!