Celery microgreens

Celery asks for more bench time than any crop in this directory: ten to eighteen days just to germinate, then three to four weeks from sowing to a cut. What you get back is not volume. It is a concentrated, aromatic seasoning green that one supplier describes as celery, but even more so.

It is also, unexpectedly, the best documented crop here on nutrition. Celery is absent from the trade's yield trial like most of this bench, so there is no measured yield to quote. But it is one of the few microgreens with its own peer-reviewed nutrient measurements, and a second study that compared the microgreen against the mature leaf across twenty genotypes. That study found four minerals higher in the mature leaf, which is not what anyone selling microgreens tends to mention.

What it is, and how to tell you grew it right

Celery microgreens are seedlings of Apium graveolens cut above the medium. They are not celery sprouts, which are eaten seed and root intact, and they are not a young stalk.

At harvest expect a small, finely textured, almost fernlike canopy of intricate divided green leaves on slender light green stems, roughly half an inch to two inches tall depending on which guide you follow. There are no thick pale stalks and there never will be. At the medium line a good tray shows many thin anchored stems with no collapsed, pinched or water-soaked bases. Nobody publishes a numeric evenness standard for celery, and given how variable the germination is, the useful confirmation is the distinct divided leaf rather than a uniform carpet.

The confusion is with cilantro and the other fine Apiaceae greens. There is no clean published visual separator: the honest tell is celery's light green stems and, more reliably, its smell. Both crops announce themselves. If you are holding a tray you did not sow, use your nose before your eyes.

What it tastes like, and what to do with it

Concentrated and unmistakably celery, and stronger than the stalk it comes from. One supplier's summary is the best one written: celery, but even more so. Another describes its own named selection as mild, so there is real range between lots, but nothing here is a neutral green.

That makes it a seasoning rather than a salad. Use it where a small quantity carries celery aroma into a dish without the stringy, watery bulk of a stalk: over seafood, on a composed salad, dropped into soup at service, or through a savory casserole. The reported flavor also holds longer than many microgreens, which is part of why chefs use it.

It is the wrong crop as the main volume in a mixed salad, and the wrong crop if what you actually wanted was crunch. The leaves and stems are tender rather than crisp, so anyone reaching for celery's texture will be disappointed by a plant that only delivers its flavor. And anyone who dislikes celery will dislike this more, not less. A concentrated version of a divisive flavor is not a way to win somebody over.

Growing it: only what differs from the standard method

Everything general about trays, medium, light and watering is on the standard tray method for growing microgreens. Celery's deltas are almost all about patience, and the crop punishes a fast-crop reflex harder than anything else here.

Ten to eighteen days to germinate. Do not uncover on a brassica schedule. This is the single most important number on the page. Where broccoli is up in two or three days, celery is still germinating a fortnight in, and one supplier warns its germination can be slower in some years than others. A tray that looks dead at day eight is not necessarily failing.

Blackout 7 to 14 days, not 2 to 3. The cover stays on until the seed has finished germinating and the shoots push it up. This is the longest blackout in the directory, and it is the crop's central risk: fine seed sitting under cover on moist medium for up to two weeks is the textbook setup for seed rot.

Sow it sparse. The seed is tiny and the instinct to sow thick is wrong here. There is no weighed per-tray rate for celery anywhere, and the calculated range from the supplier's own spacing instruction is only 1.1 to 4.4 g per 1020, a fraction of any brassica. Crowding this crop is worse than crowding a fast one: older seedlings shade younger ones in a stand that is already emerging over two weeks, and airflow falls at exactly the moment the tray most needs it.

Level unusually carefully, press for contact, and barely cover. No more than a quarter inch of medium over seed this fine, and no more than an eighth to a quarter inch of spacing between seeds. The surface must not dry out during a long germination, and it must not sit saturated either, which is a narrower target than it sounds.

After emergence, bottom water and give it 12 to 14 hours of light. Bottom watering is the specific recommendation for this crop, because keeping water off the seedlings is what limits the damping-off and bacterial problems it is described as susceptible to. It does not want more heat and it does not want more total water. It wants less surface wetting and more air.

Feed it, or use a medium that can carry it. A three to four week crop can exhaust an inert medium before harvest, and the supplier allows dilute nutrition for slow species specifically for this reason.

One temperature tension worth knowing. The crop-specific germination band is 70 to 77F, while the same supplier's general microgreen guidance warns that above 75F germination can be inhibited and disease pressure rises. Those overlap awkwardly, and nobody has resolved it with a celery trial. The practical read is to aim at the lower half of that band, around 70 to 75F, where both sources agree.

What goes wrong with celery specifically

Four failures, and the first two are both consequences of a germination period long enough to lose patience in.

Before emergence, nothing happens. Low-vigor or old seed, temperature outside the band, a dried surface, or too much water. The early sign is very few seedlings after about a week in a tray that is warm and moist. This is only partly recoverable: stabilize conditions and wait, because celery genuinely takes 10 to 18 days, but a weak lot will not become an even stand. Seed here has a dry shelf life of one to two years and one supplier reports its own supply as difficult and variable year to year.

During blackout, seed rot in a wet crowded tray. Surface watering or saturation plus poor air exchange while fine seed sits covered for up to two weeks. The early sign is stagnant wet medium, yellowing or simply non-emergent patches, or a sour smell rather than clean white roots. Catch it early by reducing wetness and restoring airflow. Discard a tray with spreading rot.

After emergence, damping-off. Pythium and Rhizoctonia favored by wet conditions and compounded by slow dense growth. Stems go water-soaked and constricted at or just below the medium line and plants topple. Early losses can be contained by correcting drainage, irrigation, temperature and spacing. A spreading collapse is not a safe crop to salvage.

Through grow-out, an uneven shaded stand. Too much seed. Taller older seedlings shade the smaller ones and airflow drops. Improving light and airflow helps, but the uneven cut is already a quality loss you cannot recover.

Nutrition, and what is actually established

Celery is the rare crop here where this section has real numbers in it, and they are worth reading closely because they do not say what the category says.

There is no USDA record. FoodData Central was searched for "celery microgreens" on 2026-08-08 and returned nothing, so there is no FDC identifier or nutrient panel, and mature celery entries are not a substitute.

What exists is peer-reviewed. A 2012 analysis of 25 commercially grown microgreens included green Apium graveolens, grown mostly in soil in an unheated greenhouse under ambient light, in three replicates. It measured celery at 6.8 percent dry matter, 45.8 mg of total ascorbic acid per 100 g fresh weight, 5.6 mg of beta-carotene per 100 g, 5.0 mg of lutein and zeaxanthin per 100 g, 2.6 mg of violaxanthin per 100 g, and 2.2 micrograms of vitamin K1 per gram.

Then the finding that matters most to a reader. A 2022 study compared twenty celery genotypes at the microgreen stage against the mature leaf across ten minerals. Nitrogen, phosphorus, calcium, sodium and sulfur came out higher in the microgreens. Potassium, zinc, copper and manganese came out higher in the mature leaves. Iron showed no significant difference.

That is a direct, measured counterexample to the claim the whole category runs on. "Microgreens are more nutritious than the mature plant" is not a rule; on celery it is true for five minerals and false for four. Anyone quoting you a blanket multiplier, and the marketing language around this crop does reach for 10 to 50 times, is not describing this data. Neither study supports a nutrition label or a health outcome, and none of these numbers should be converted into a disease-prevention claim.

If you are eating celery microgreens, eat them because they taste strongly of celery. That is a good enough reason and it is the one the evidence supports.

Which seed to buy

The commercial set is thin, and only one selection is actually named.

Cutting Celery is the one named product: open-pollinated, light green stems, intricate green leaves, a mild celery flavor, 26 to 30 days, and marked as a hydroponic performer. Everything else sold as celery microgreen seed is generic Apium graveolens with no named cultivar and no measured difference in stem length, color, days or yield. A pair of research breeding lines with superior mineral performance appear in the literature, but no retailer sells them as microgreen seed, so they are not an option.

Specify untreated seed explicitly, from a supplier listing it for microgreen or food use, with lot and germination test information if you are buying volume. Refuse dyed, fungicide-treated, insecticide-treated or undisclosed-treatment seed: extension guidance is that treatments may be present in the young shoots and should not be eaten. Outdoor-sowing vegetable seed is the specific thing to watch for here, because celery seed is widely sold for gardens.

A bad lot on this crop is expensive in a way it is not elsewhere. It presents as very slow, patchy emergence in a crop already expected to take 10 to 18 days to germinate, so a grower blames the room, the temperature and themselves before suspecting the seed. Meanwhile it holds a tray and a rack position for weeks and ends as an uneven cut. Run a small germination test before committing a production wave, and keep the lot number.

Is it worth growing?

For the right buyer, yes, and it is one of the clearest specialist crops in the directory.

Grow it if somebody specifically wants celery aroma as a garnish and you can accept three to four weeks of tray time, small tender plants, and setting your own density by trial. Chefs, specialty market growers, and patient home growers who want the flavor without growing stalks are the audience. The wild-celery warning is a real point in its favor too: a sown tray of labeled seed gives you celery aroma with none of the identification risk that makes foraging the umbellifers genuinely dangerous.

Do not make it your first tray. A beginner needs feedback, and this crop offers none for two weeks. And do not build a weight-based business around it, because you would be pricing a crop with no published yield per tray at all.

For a tray slot it competes with cilantro most directly, and with the fast brassicas whenever the buyer's real requirement is reliability. Cilantro wins when the aroma wanted is cilantro, and it wins on evidence too: it is the only Apiaceae crop in the trade's yield trial, at 26 g of seed, 6 oz and 20 days. Radish and broccoli win outright when speed, a known per-tray yield or salad volume matter, at 8 to 12.5 days and 8 to 11.5 oz. Celery wins only when its exact aroma and that intricate leaf are the point, and that is a narrower case than most crops here, honestly stated.

A note on the numbers above

The seed rate is arithmetic, not a measurement, and it is labeled that way on purpose. Johnny's publishes an eighth to a quarter inch spacing and 1,311,000 seeds per pound. Across a 200 square inch 1020 that is roughly 3,200 to 12,800 seeds, which is 1.1 to 4.4 g. Every step of that is checkable and none of it is a trial. It is a four-fold interval, which is the honest width of the uncertainty, and it is why the instruction is to start sparse and weigh your own.

Celery cannot complete the comparison table, and it is the third crop that cannot.

A blank means nobody has published that figure. Every crop here has a full research file; where no measured number exists this site leaves the cell empty rather than repeating an estimate. How the numbers work

All 61 crops, sortable, on the microgreen comparison.

Celery's calculated cost per tray, 14 to 58 cents, overlaps carrot and dips below it at the sparse end. Corrected 2026-08-11: this paragraph used to say carrot kept the cheapest-tray title anyway, which contradicted the carrot page's own correction and four other entries. Celery's 14 cents is the lowest figure published here. What is true, and worth keeping, is that it is the lowest CALCULATED one: celery's rate came from a ruler and carrot's came from a production record, so carrot holds the cheapest MEASURED tray. That distinction is worth more than the ten cents between them.

And here is the pattern this crop makes visible. The Apiaceae bench, carrot, celery, dill, fennel, chervil and cilantro, is almost entirely unmeasured. Cilantro is the only one of the six that appears in the trade's yield trial, which is why it is the only one with a yield, a tested seed rate and a real cost per tray. Every other fine aromatic crop in that family is sold with confident day counts and no weight behind any of them. That is not a coincidence about this site's research; it is the shape of what has been published, and it is worth knowing before you plan a bench around any of them.

Sources

• Johnny's Selected Seeds, Cutting Celery microgreen seed (922M) - the named selection at 26 to 30 days, finely textured intricate leaves on light green stems, mild celery flavor, 1/8 to 1/4 inch spacing, 1,311,000 seeds per pound, 5 to 10 refrigerated days, the dilute-nutrition allowance for slow species, the above-75F warning, and the $59.45/lb price behind the seed cost, listed 2026-08-08.
• The Seed Collection, celery microgreens grow guide - 10 to 18 days to germinate at 21 to 25C, 21 to 28 days sowing to harvest, no soak, and true-leaf harvest at 2 to 6 cm.
• True Leaf Market, celery microgreens seeds - 21 to 28 days, darkness for about 7 to 14 days to complete germination, no more than a quarter inch of medium over the seed, and the advice to use microgreen-specific or organic seed rather than treated outdoor vegetable seed.
• Epic Gardening, celery microgreens - the optional 24 to 48 hour soak for difficult germination, 12 to 14 hours of light after emergence, bottom watering to limit damping-off and bacterial growth, hull retention as a hat and brushing it off, possible regrowth from tops-only clipping, the crowding and shading failure, and very fine root hairs mistaken for mold.
• Sproutpeople, celery micro-greens - "celery, but even more so", exceptionally slow and year-to-year variable germination, difficult seed supply, and a 1 to 2 year dry seed shelf life.
• Johnny's microgreens comparison chart (PDF) - Cutting Celery placed in the 26 to 30 day slow-growing group.
• Johnny's microgreens yield trial results (PDF) - the 29-variety table that contains no celery, and the cilantro, radish and broccoli comparison figures.
• Johnny's yield trial, method and discussion - weighed per-1020 rates harvested at first true leaf, and the warning that yields do not translate perfectly between systems.
• USU Extension, grow your own microgreens - the general 2 to 5 lb top-tray weight used to drive roots down, which is not celery-specific.
• UC IPM, damping-off - Pythium and Rhizoctonia rotting seedlings at or below the soil line, and cool wet conditions favoring some Pythium species.
• Xiao et al., Journal of Agricultural and Food Chemistry, 2012 (PDF) - 25 commercially grown microgreens including green Apium graveolens: 6.8 percent dry matter, 45.8 mg/100 g total ascorbic acid, 5.6 mg/100 g beta-carotene, 5.0 mg/100 g lutein and zeaxanthin, 2.6 mg/100 g violaxanthin, 2.2 micrograms/g phylloquinone.
• Singh et al., 2022, celery microgreen and mature leaf mineral comparison - twenty genotypes across ten minerals: N, P, Ca, Na and S higher in the microgreens, K, Zn, Cu and Mn higher in the mature leaves, no significant iron difference, and the PAU2, PAU4 and PAU16 breeding lines.
• SDSU Extension, growing microgreens at home - seed treatments may be present in the young shoots and should not be consumed.
• USDA FoodData Central - searched for "celery microgreens" on 2026-08-08, no record located.