Pea microgreens, often called pea shoots, are the tender young leaves, stems, and tendrils of the pea plant, harvested long before they produce pods. They are distinct from sprouts, which are germinated only in water and consumed whole, including the root and seed. These greens offer a sweet, fresh, pea-like flavor and contain high levels of vitamins A, C, and K, along with fiber and antioxidants. Their rapid growth cycle, typically yielding a harvest in 10 to 14 days, makes them an accessible crop for beginners looking to grow fresh produce indoors.
Preparation and Soaking the Seeds
The growing process begins with selecting the appropriate materials, specifically shallow growing trays: one with drainage holes and a second solid tray for bottom watering. A fine-particulate growing medium, such as coco coir or a sterile seed-starting mix, provides the necessary anchor for the robust pea root system. It is not necessary to use a nutrient-rich medium because the pea’s large seed provides all the initial energy the microgreen needs.
The pea seed possesses a thick seed coat that resists water, requiring soaking to trigger germination. Soaking softens the hull, allowing the internal embryo to absorb water and break dormancy. An ideal soaking duration is 8 to 12 hours in cool water, with a maximum of 24 hours to prevent the seeds from drowning or beginning to ferment. After soaking, the seeds should be thoroughly rinsed and drained to remove residual sugars that could encourage mold growth.
The prepared growing medium should be moistened to the consistency of a wrung-out sponge, ensuring it is damp but not saturated.
Sowing and the Germination Phase
Sowing density is important for a successful pea microgreen crop, aiming for a thick, carpet-like layer of seeds without significant overlap. For a standard 10×20 inch growing tray, this density typically requires between 200 to 260 grams of dry seed. The soaked seeds are spread evenly across the surface of the pre-moistened medium and gently pressed down to ensure every seed has firm contact with the substrate.
Weighted Germination
The germination phase is immediately followed by a weighted period. A second tray, often weighted with a 7 to 15 pound object, is placed directly on top of the seeded tray for the first two to four days. This pressure forces the emerging radicles—the first roots—downward into the medium, establishing a strong anchor and ensuring uniform growth.
Blackout Phase
After the weighted period, the trays enter the blackout phase, which continues the dark, humid environment but without the weight. This phase encourages etiolation, causing the seedlings to stretch upward in search of light, resulting in taller, more tender stems. The seedlings are ready to emerge from darkness when they have grown to a height of about one to two inches and begin to visibly lift the top tray.
Active Growth: Light, Air, and Watering
Once the seedlings have lifted the cover tray, they are moved into a well-lit area for the active growth stage, which lasts approximately four to seven days. Adequate light exposure is necessary for photosynthesis, stimulating the production of chlorophyll that turns the shoots a vibrant green color. Pea microgreens thrive under full-spectrum grow lights positioned six to twelve inches above the canopy for 12 to 16 hours each day.
The distance between the light source and the plants is important; too far results in weak, leggy growth, while too close can cause the tender leaves to burn. The use of red wavelengths can enhance the natural sweetness of the pea shoots. Maintaining an ambient temperature between 10 to 23°C (50–73°F) promotes healthy, rapid growth.
Proper watering is managed exclusively from below to prevent moisture from settling on the dense canopy, which creates an ideal environment for mold and fungal growth. The tray with drainage holes is nested within the solid bottom tray, and water is added to the lower tray, allowing it to soak up through the medium via capillary action. This bottom-watering technique encourages the roots to grow deep and keeps the delicate leaves dry.
Good air circulation is required to control humidity and prevent disease. A small oscillating fan should move air gently across the surface of the greens, strengthening the stems and aiding moisture evaporation. Stagnant air is the primary cause of crop loss.
Harvesting and Usage
Harvesting
Pea microgreens are typically ready for harvest between 10 and 14 days after sowing, determined primarily by their height and leaf development. The optimal time to cut is when the shoots are three to four inches tall and the first set of true leaves is just starting to emerge from between the initial cotyledon leaves. Harvesting at this stage ensures the best flavor and texture before the stems become overly fibrous.
The day before harvesting, withhold all water, allowing the greens to dry out slightly, which improves their shelf life after cutting. A clean, sharp knife or pair of scissors should be used to make a uniform cut just above the soil line, avoiding any contact with the growing medium. This technique maximizes the harvested yield while keeping the greens clean. Pea microgreens are one of the few varieties that can sometimes produce a small second harvest if cut carefully above the lowest leaf node.
Usage and Storage
The harvested shoots should not be washed until immediately before use, as excess moisture significantly shortens their freshness. Storing the unwashed shoots in an airtight container in the refrigerator will keep them crisp for up to one week. They are versatile and can be enjoyed raw in salads and sandwiches, blended into smoothies, or lightly wilted into stir-fries.