Microgreens are young, edible seedlings of vegetables and herbs, harvested shortly after their first leaves (cotyledons) have fully developed. Unlike sprouts, which are germinated seeds consumed whole and grown in water, microgreens are grown in a medium like soil or a fiber mat, requiring light and air circulation. Only the stem and leaves are eaten. The seeds used are specific, high-quality varieties of common vegetables grown under specialized conditions.
Biological Roots: Which Plants Yield Microgreen Seeds?
The seeds used for microgreens originate from a wide array of plant species across several major botanical families.
- The Brassicaceae family includes pungent options such as radish, cabbage, broccoli, and arugula, favored for their quick growth cycle and concentrated nutrient profile.
- The Poaceae family (grasses) provides seeds for wheatgrass, barley, and oat microgreens.
- The Lamiaceae family yields herbaceous choices like basil and mint.
- The Apiaceae family gives rise to cilantro, fennel, and parsley microgreens.
- The Asteraceae family, such as sunflower and various types of lettuce, are widely used for their distinct textures and flavors.
Seed Production: How Are Microgreen Seeds Grown and Harvested?
The production of microgreen seeds is a specialized agricultural process, differing significantly from seeds intended for mature field crops. They are grown on a large scale in specific regions where consistency and purity are paramount to ensure a uniform final product. Parent plants are carefully cultivated to maximize seed viability and genetic quality before harvest.
After harvest, seeds undergo rigorous cleaning to remove debris and contaminants. Microgreen seeds must be sold in an untreated state, meaning they cannot have fungicides or pesticides applied to their exterior, which is common practice for conventional agricultural seeds. Since microgreens are consumed raw, chemical treatments on the seed could transfer to the edible portion of the plant.
Because seeds must be untreated, pathogen testing is a non-negotiable step in the supply chain. Reputable seed suppliers test each lot for human pathogens like Salmonella, E. coli, and Listeria before they are sold for microgreen production. Testing is critical because the warm, humid conditions ideal for microgreen growth are also conducive to the proliferation of these bacteria. The seed producer must provide a Certificate of Analysis to demonstrate that the seeds meet strict food safety standards.
Sourcing Specialized Seeds: Why Quality Matters
The commercial side of the microgreen industry requires seeds that are fundamentally different from those found in a typical garden center. Standard garden seeds are usually packaged in small quantities and are not guaranteed to have the high germination rate necessary for dense microgreen planting. Microgreen growers purchase seeds in bulk, often in pounds or larger amounts, to manage costs for their high-density planting methods.
The viability of a seed lot is a key quality marker, with specialty microgreen suppliers aiming for a germination rate of 90% or higher. A low rate results in patchy trays and wasted growing space, directly impacting yield and profitability. Specialty vendors also provide traceability, including lot numbers and pathogen testing results, which are necessary for commercial food safety compliance.
Home growers and commercial operations benefit from choosing specialized suppliers who understand the need for untreated, high-viability seeds. Seeds purchased from general retailers may have been treated or stored improperly, leading to poor performance. Once purchased, seeds must be stored correctly to maintain viability, ideally in food-grade airtight containers in a cool environment (40 to 50 degrees Fahrenheit) with low humidity. Proper storage prevents moisture absorption and temperature fluctuations that can degrade the seed embryo.