Microgreens are nutrient-dense seedlings that NASA is actively researching as a food source for astronauts on long-duration space missions - Short 2/9/2026

February 9, 2026

Microgreens are nutrient-dense seedlings that NASA is actively researching as a food source for astronauts on long-duration space missions

NASA is experimenting with these greens as a solution to feed astronauts.

They are 4–40 times higher in key vitamins.

One variety has some of the highest levels of sulforaphane — a cancer-fighting compound — in any produce.

And on top of that these super plants only take 10 days to grow.

These are microgreens — seedlings that are harvested before they grow up. Would you eat baby plants?

Sources

NASA Is Researching Microgreens for Space Missions

NASA Science. "How Do You Harvest Microgreens in Microgravity?" NASA Science Research, May 2025. Available: https://science.nasa.gov/science-research/science-enabling-technology/how-do-you-harvest-microgreens-in-microgravity/

NASA's Kennedy Space Center has developed candidate approaches for growing and harvesting microgreens in microgravity and tested them on parabolic flights. The article states that "microgreens are small, densely grown, young plants that have great potential as space crops" and notes that packaged food quality degrades over long durations, making fresh crops essential.

Johnson, C.M. et al. "Microgreens for Human Nutrition in Spaceflight." NASA Technical Reports Server (NTRS), 2019. Available: https://ntrs.nasa.gov/citations/20190033178

This NASA literature review specifically examined microgreens as a dietary supplement for astronauts. It states that "traditional crops can take months to mature, but microgreens are ready to harvest within two weeks, and they can be grown in small volumes," making them practical for spaceflight where crew time, power, mass, and volume are limited.

Kyriacou, M.C., Rouphael, Y., Di Gioia, F. et al. "Microgreens as a Component of Space Life Support Systems: A Cornucopia of Functional Food." Frontiers in Plant Science, 8:1587, 2017. Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC5600955/

This peer-reviewed paper examines microgreens as candidates for space life support systems. It notes that microgreens "are ideal for space flight environments as they can be harvested directly by crew members, ensuring freshness and high quality" and that their production can be implemented on shallow substrates with minimal nutrient supplementation.

USDA Agricultural Research Service. "Growing Plants in Space." Available: https://www.ars.usda.gov/oc/utm/growing-plants-in-space/

USDA plant physiologist Dr. Raymond Wheeler, who collaborates with NASA, confirms that "current collaborations include research on microgreens as a food crop" for space applications. He states that astronauts are already growing and consuming fresh crops on the International Space Station.

Microgreens Contain 4–40 Times Higher Concentrations of Key Vitamins

Xiao, Z., Lester, G.E., Luo, Y., & Wang, Q. "Assessment of Vitamin and Carotenoid Concentrations of Emerging Food Products: Edible Microgreens." Journal of Agricultural and Food Chemistry, 60(31): 7644–7651, 2012. Available: https://pubmed.ncbi.nlm.nih.gov/22812633/

This is the landmark study. Researchers at the University of Maryland and USDA analyzed 25 commercially available microgreens for vitamins C, E, K, and beta-carotene. They found that "microgreen cotyledon leaves possessed higher nutritional densities" than mature leaves, with concentrations ranging from 4 to 40 times higher depending on the variety and nutrient measured. Red cabbage, cilantro, garnet amaranth, and green daikon radish had the highest concentrations of ascorbic acid, carotenoids, phylloquinone, and tocopherols, respectively.

USDA Agricultural Research Service. "Specialty Greens Pack a Nutritional Punch." January 2014. Available: https://www.ars.usda.gov/news-events/news/research-news/2014/specialty-greens-pack-a-nutritional-punch/

The USDA's own summary of the Xiao et al. study reports that "in general, microgreens contained considerably higher levels of vitamins and carotenoids — about five times greater — than their mature plant counterparts." The article notes that total vitamin C ranged from 20 to 147 mg per 100 g of fresh weight depending on species.

University of Maryland College of Agriculture & Natural Resources. "Mighty Microgreens." Available: https://agnr.umd.edu/news/mighty-microgreens

The university's own reporting on the study quotes researcher Qin Wang: "We were really surprised." Graduate student Zhenlei Xiao added: "Some of the numbers were really, really high. We thought it might have been a mistake but we double-checked so many times and there were no mistakes."

Broccoli Microgreens Are Among the Highest Produce Sources of Sulforaphane

Bouranis, J.A., Beaver, L.M., et al. "Sulforaphane Bioavailability in Healthy Subjects Fed a Single Serving of Fresh Broccoli Microgreens." Foods, 12(20): 3784, 2023. Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC10606698/

This study confirmed that "broccoli microgreens are a significant source of SFN [sulforaphane]" and that Brassicaceae microgreens, particularly broccoli microgreens, are "good sources of minerals and antioxidant phytochemicals, including isothiocyanates." The study notes that broccoli sprouts (3–5 day-old plants) "contain one of the highest concentrations of GRN [glucoraphanin, the sulforaphane precursor] compared to mature plants," and that microgreens are similarly rich in this content.

Fahey, J.W., Zhang, Y., & Talalay, P. "Broccoli sprouts: An exceptionally rich source of inducers of enzymes that protect against chemical carcinogens." Proceedings of the National Academy of Sciences, 94(19): 10367–10372, 1997. Available: https://pubmed.ncbi.nlm.nih.gov/9294217/

The foundational Johns Hopkins study that established young broccoli plants as exceptional sources of sulforaphane. Researchers found that broccoli sprouts contained 20 to 50 times the concentration of chemoprotective compounds (glucosinolates including glucoraphanin) found in mature broccoli heads. This research established young Brassica plants — including microgreens harvested at a slightly later stage — as among the highest produce sources of sulforaphane precursors.

Fahey, J.W., Talalay, P., & Kensler, T.W. "Notes from the Field: 'Green' Chemoprevention as Frugal Medicine." Cancer Prevention Research, 5(2): 179–188, 2012. Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC6804255/

This review confirms that on a weight basis, glucoraphanin (the sulforaphane precursor) is most abundant in the seeds of the broccoli plant, with young plants (sprouts and microgreens) containing dramatically higher concentrations than mature broccoli. The capacity to induce protective enzymes follows the same curve as glucoraphanin concentration, confirming that younger Brassica plants are among the most potent produce sources of this compound.

Microgreens Are Harvested in 7–14 Days

Johnson, C.M. et al. "Microgreens for Human Nutrition in Spaceflight." NASA Technical Reports Server (NTRS), 2019. Available: https://ntrs.nasa.gov/citations/20190033178

States that microgreens "are ready to harvest within two weeks" after planting. This rapid turnaround is one of the key reasons NASA considers them practical for spaceflight.

Defines microgreens as "immature versions of vegetables, herbs and other plants harvested anywhere from a week to two weeks after germination." The study's microgreens were harvested at the cotyledon stage, consistent with the 7–14 day timeframe. The "10 days" referenced in the video falls within this established range.

Confirms that microgreens have "short growth cycles" and describes sowing rates and harvest timing consistent with 7–14 day production. Notes that ease of germination varies by species, with some benefiting from pre-sowing treatments to standardize and shorten the production cycle.

Notes

The "4–40 times" figure specifically refers to concentrations of vitamins C, E, K, and beta-carotene as measured in the Xiao et al. 2012 study. This is not a blanket statement about all nutrients — it applies to the specific vitamins and carotenoids that were analyzed. The USDA's average across all 25 varieties was approximately 5 times higher. We say "key vitamins" in the video to keep this accurate without overreaching.

Regarding sulforaphane: broccoli sprouts (3–5 days old) technically have the highest measured concentrations of sulforaphane precursors among produce. Broccoli microgreens (7–14 days) are similarly rich and are confirmed as a "significant source." The script says "some of the highest levels... in any produce," which is accurate and does not claim microgreens are the single highest source.

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