Microgreens vs baby greens: days, nutrients, and tray or pot

Microgreens and baby greens are salad plants cut at two different ages: Penn State Extension gives 7 to 21 days for microgreens, and Colorado State University Extension gives 21 to 28 days for baby leafy greens. Pick microgreens for speed and a shallow tray on a shelf. Pick baby greens for a salad base from a pot that you can cut more than once. Neither is the more nutritious on every count, and the studies that compare them say so.

The difference is the age at cutting

Penn State Extension says microgreens can be harvested from 7 to 21 days after germination, once the seed leaves (cotyledons) have fully developed and the first true leaves have emerged, by cutting the seedlings at the base just above the growing medium. Purdue Extension puts the height at 2 to 4 inches for most crops. These are the cut-and-eat tray crops covered in how to grow microgreens at home.

A baby green is a plant that has gone on to make real leaves and is cut while those leaves are still small. A Colorado State University Extension fact sheet lays out the ladder: microgreens at 7 to 21 days and about 2 inches, baby leafy greens at 21 to 28 days and 3 to 4 inches, and mature leafy greens at 45 to 60 days. Baby leaf is not a sprout either; sprouts are a separate, higher-risk product.

Timing in research trials runs longer than the extension ranges, and the gap between the stages widens. In a trial of three wild leafy species grown hydroponically, Lenzi and colleagues (Foods, 2019) cut microgreens 14 to 16 days after sowing and baby leaves 35 to 43 days after sowing. In a 2023 study of five vegetable crops, Mallor and colleagues cut microgreens at 25 to 30 days and baby plants at 50 to 60 days. Species, light and temperature move these numbers, so treat the extension ranges as the home target.

Yield: what a pot gives you against a tray

Per square metre of hydroponic bench, baby leaf won in one study. Lenzi and colleagues (Foods, 2019) report that, on average across three wild species, the baby leaf stage gave 2.11 kg fresh weight per square metre against 0.99 kg for microgreens. It was not universal: salad burnet (Sanguisorba minor) yielded more as microgreens than as baby greens. Hydroponic benches are not a windowsill tray, so read it as a direction that varies by crop rather than a number to plan around.

Baby greens have one advantage microgreens do not share in the same way: repeat cuts. The University of Maryland Extension describes cut-and-come-again lettuce as plants cut just above ground level with scissors at 6 to 10 inches tall, which regrow if watered and fertilized and are ready for a second cut 2 to 3 weeks later. That is a larger plant than a baby leaf, so treat it as the upper end of the method. Whether a microgreens tray gives a second cut is its own question, answered in do microgreens regrow. For grams per tray by crop, see microgreens yield per tray.

Taste and texture

Microgreens are meant to be cut early for a reason beyond speed. Purdue Extension notes that microgreens generally become bitter the longer they grow, and says this is especially true for sunflowers. A tray left a week too long drifts toward a tougher, more bitter green.

Baby leaf is cut as whole, small true leaves, which is why Colorado State’s fact sheet lists it as a separate product from microgreens, with its own size (3 to 4 inches) and its own timeline. Grow it if what you want is a salad base rather than a garnish.

Nutrients: what each study measured

The figure most people quote comes from USDA. The Agricultural Research Service tested 25 microgreens and reported that, in general, they contained about five times the vitamins and carotenoids of their mature plant counterparts. The ARS write-up also lists the vitamin C range, 20 to 147 mg per 100 g of fresh weight depending on the species, and warns that growing, harvesting and handling conditions may have a considerable effect. The comparison in that work is with mature plants. It does not say microgreens beat baby leaf. The wider picture, including how the more dramatic “40 times” figure was narrowed, is in what the microgreens nutrition evidence shows.

Two studies that did put the stages side by side give a mixed answer:

• Five crops at three stages. Mallor and colleagues (Foods, 2023) measured chard, spinach, lettuce, borage and chicory as microgreens, babies and mature plants. For vitamin C, spinach and chard were highest at the baby stage, while borage, chicory and lettuce were mostly highest as microgreens. For carotenoids, baby plants generally came lower than microgreens, and lettuce babies were lowest. The authors also found mature plants lower than both young stages for fatty acids, carotenoids, tocopherols, vitamin C, polyphenols and antioxidant activity.
• Three wild species. Lenzi and colleagues compared microgreens and baby leaves of salad burnet, Sinapis arvensis and dandelion grown in a nutrient solution. They found the pattern depended on the species. Nitrate was significantly higher in baby greens than in microgreens overall, but the interaction with species mattered: dandelion microgreens were much lower than dandelion baby greens, while salad burnet and Sinapis arvensis were similar at the two stages.

So a claim that microgreens are healthier than baby greens holds for some crop and nutrient pairs and fails for others. Spinach for vitamin C is a case where the baby stage led in that study. These are lab measurements of composition, not health outcomes for a person who eats them.

Tray or pot: the space you need

A microgreens crop fits a shallow tray. Illinois Extension calls a container 1 to 2 inches deep ideal for microgreens if you want to save on soil, and sizes its seeding rates for a standard 10 by 20 inch flat. If you are choosing one, you can browse 10x20 microgreen trays on Amazon and check the depth against that 1 to 2 inch figure.

Baby greens want a pot. Oregon State Extension says containers are ideal for lettuce and other greens, and that greens have shallow roots but need 7 to 8 inches of fertile soil. Oregon State also treats baby greens as young seedlings thinned from a bed: cut at ground level, leaving the rest room to grow. The width and spacing arithmetic for a lettuce pot is in lettuce container size, and the cool-season mix to put in it is in growing salad greens in containers this fall. University of Maryland Extension adds that baby leaf lettuce can be grown entirely in indirect light in summer.

Per-tray running costs for microgreens, seed, substrate and light, are worked through in microgreens cost per tray.

Which one to grow

• Choose microgreens if you want something on the plate in the 7 to 21 days Penn State Extension gives, have only a shelf or a windowsill, and are happy to start a fresh tray for each harvest.
• Choose baby greens if you want a salad base, have room for a pot 7 to 8 inches deep or more, and would like to cut the same planting more than once.
• Grow both if you have the space: a tray cut within Penn State’s 7 to 21 days covers the wait while a pot of baby greens grows to Colorado State’s 21 to 28 days.

Sources

• Penn State Extension: The ABCs of Microgreens
• Colorado State University Extension: Sprouts, Microgreens and Leafy Greens fact sheet
• Purdue Extension: Grow Microgreens at Home
• University of Illinois Extension: Growing Microgreens
• Oregon State University Extension: Growing Lettuce & Other Greens
• University of Maryland Extension: Growing Lettuce in a Home Garden
• USDA Agricultural Research Service: Specialty Greens Pack a Nutritional Punch
• Mallor et al. (2023), Foods: Nutraceutical Potential of Leafy Vegetables Landraces at Microgreen, Baby, and Adult Stages of Development
• Lenzi et al. (2019), Foods: Antioxidant and Mineral Composition of Three Wild Leafy Species, a Comparison Between Microgreens and Baby Greens