The Food Safety Modernization Act (FSMA) includes specific rules for farms growing sprouts that include rigorous testing of irrigation water, but there may be some confusion among growers about what constitutes a “sprout” versus a “microgreen”.
On page 74497, Comment 363, the rule defines sprouts as “usually harvested when the cotyledons (or seed leaves) are still un- or under-developed and true leaves have not begun to emerge.” In regard to microgreens, it goes on to say that “In contrast, microgreens reach a later stage of growth, typically associated with the emergence of ‘true’ leaves”.
If you are growing sprouts, and not microgreens, the rule is specifically targeting “growing, harvesting, packing, and holding of all sprouts, except soil- or substrate-grown sprouts harvested without their roots”. If you are growing pea shoots, cutting the top part of the plant, and discarding the seeds, roots, and media that they are grown in, then these are not included in the FSMA definition of “sprouts”.
Some farms sell certain microgreens or sprouts, like wheatgrass, to their customers while still in their trays to be harvested by the customers. The FDA’s Sprout Guidance Document in section C. states that they will “exercise enforcement discretion” for this practice, provided that the grower “annually collects written assurances” from the customer, stating that “the sprouts will be cut above the soil or substrate line before use”. Microgreens and sprouts harvested above the soil line are considered “covered produce”, so while they would not be held to the same standard as sprouts, they would need to be treated the same as other produce grown for human consumption.
Note that while the FDA does not require it, they recommend that microgreen growers and growers producing sprouts harvested above the soil line consider voluntarily adhering to the same practices that are covered by sprouts under the FSMA rule.
If you are unsure about whether or not your farm needs to comply with FSMA, use the UNH Cooperative Extension Online Tool for Produce Growers.
You can read more about sprout production guidance in the FDA's Sprout Guidance document.