Arugula microgreens are fast, peppery greens you can harvest in about 6–14 days. Sow about 10 grams of seed per 10 x 20 inch (25 x 51 cm) tray with no soaking, keep it covered for 1–2 days, then grow under moderate light. Arugula is one of the cheapest microgreens to grow, at about $0.17 of seed per tray in Utah State’s bulk pricing, and it tolerates lower light than most crops.
Key takeaway: Arugula is a top pick for spicy flavor on a budget. Use a light hand with seed, keep it cool and airy, and harvest early for the best bite.
| Arugula microgreens at a glance | Value | Source |
|---|---|---|
| Seed per 10 x 20 in (25 x 51 cm) tray | 10 g | Johnny’s; Utah State |
| Presoak | No | Utah State |
| Covered time | 1–2 days | Utah State |
| Days to harvest | 6–14 days | Virginia Tech; Utah State 6–8; Johnny’s 14 |
| Light target | DLI about 9 mol/m²/day | Virginia Tech (Allred and Mattson 2024) |
| Yield per tray | About 10 oz (283 g); 0.33 lb (147.6 g) in Penn State’s unlit greenhouse | Johnny’s; Penn State |
| Flavor | Spicy, nutty, peppery | Johnny’s; Utah State |
Why Grow Arugula Microgreens?
Arugula (Eruca sativa), also called rocket, belongs to the cabbage family. Virginia Cooperative Extension notes arugula has a peppery or spicy taste while most brassicas are more neutral, which makes arugula microgreens a strong flavor accent. They’re also generous: Maryland Extension says 1 tablespoon of arugula seed sown in a 10 x 20 inch (25 x 51 cm) tray produces about 8–12 cups of microgreens. Johnny’s lists its microgreen arugula with purple stems and a spicy, nutty flavor.
How to Grow Arugula Microgreens
- Prepare the tray. Fill a tray with drainage holes with 1–1.5 inches (2.5–4 cm) of moist coir or seed-starting mix, or use a soaked hemp mat.
- Weigh 10 g of seed. Arugula seed is small, so a little goes a long way.
- Sow evenly. Scatter seed over the surface and press lightly. Small, dark seeds are hard to see on dark media, as Maryland points out, so sow slowly in passes.
- Mist and cover. Mist the surface and cover with another tray. A light weight helps roots grip.
- Uncover in 1–2 days. Arugula sprouts quickly; brassicas can germinate in about 36 hours at 72°F (22°C), according to Maryland.
- Give light. About 16 hours a day with the lamp 6–12 inches (15–30 cm) above the leaves.
- Bottom water. Add water to the bottom tray to keep leaves dry.
- Harvest at 6–14 days. Cut above the media when the cotyledons are open.
Light: Arugula Tolerates Less
Maryland Extension notes that lettuce, arugula, mustards and Asian greens grow acceptably well in less-than-ideal light, which makes arugula a good choice for a windowsill. Virginia Tech’s guide cites research suggesting a DLI of about 9 mol/m²/day for arugula, lower than the 12 or more suggested for mustard and mizuna. That’s about 150 µmol/m²/s for 16 hours. Brighter light gives sturdier, more colorful stems, while too little light gives thin, leaning seedlings. See microgreens light requirements.
Temperature and Airflow
Penn State recommends soil temperatures of 60–75°F (16–24°C) for germinating microgreens and air temperatures of 60–70°F (16–21°C). Arugula likes the cooler end, and warm, still air is a recipe for mold in dense trays. Run a small fan nearby and vent covers, as Maryland suggests, to keep humidity from building. See microgreens mold.
When to Harvest Arugula Microgreens
Harvest when the two heart-shaped cotyledons are fully open and the first lobed true leaf is just appearing. Johnny’s harvested its trial at the first true-leaf stage at about 14 days; Utah State’s faster indoor schedule gives 6–8 days. Cutting earlier gives a milder taste; waiting gives a hotter, more mature arugula flavor and leafier texture. Johnny’s notes that each day makes a big difference in size and yield. See how to harvest microgreens.
Arugula Microgreens Yield and Cost
| Source | Seed per tray | Yield per tray | Days |
|---|---|---|---|
| Johnny’s 2017 trial | 10 g | About 10 oz (283 g) | 14 |
| Penn State greenhouse, no supplemental light | 10–15 g | 0.33 lb (147.6 g) | About 14 |
| Utah State indoor guide | 10 g | — | 6–8 |
Johnny’s says one ounce (28 g) of arugula seed sows about three flats. Utah State lists seed cost at about $0.17 per tray at bulk prices, one of the lowest in its table. Record your own seed weight and harvest weight each time. See microgreen seed density.
Common Problems
- Mold in the center of the tray: seed sown too thick or air too still. Lower density and add airflow.
- Stretching and flopping: too little light or covered too long. Uncover once most seeds sprout.
- Very bitter taste: harvested late or grown hot. Cut earlier and keep the room cooler.
- Patchy stand: uneven sowing or old seed. Sow in two passes at right angles.
Storing and Using Arugula Microgreens
Store unwashed arugula microgreens in a sealed container in the fridge and wash right before eating. Penn State reports microgreens stored at 41°F (5°C) in the dark can last 10–14 days, versus 2–4 days at room temperature. Use them on pizza after baking, in sandwiches, on eggs, in pasta and grain bowls, or as a peppery salad base. See how long microgreens last.
Arugula Microgreens vs Baby Arugula
Baby arugula is grown longer, cut at several inches tall, and can regrow for a second or third cut, as Maryland notes for baby greens. Arugula microgreens are cut once at the seedling stage, in a fraction of the time and space. If you want both, grow a tray of microgreens for quick harvests and a hydroponic bucket or raft of arugula for baby leaves. See can you regrow microgreens and best microgreens to grow.
Planning Arugula Trays for a Steady Supply
Johnny’s 2017 trial harvested arugula at about 14 days from roughly 10 g of seed, with a yield of about 10 oz (283 g) per 10 x 20 inch (25 x 51 cm) tray. Because the crop is quick, a single tray every week is enough for most households. Sow a new tray every 7 days so one is always growing while you eat from the last. Arugula also finishes in about the same window as kale, broccoli and red cabbage in that trial, so you can grow them side by side under the same light and cut them on the same day for a mixed salad.
Keep notes on each tray: sowing date, seed weight, days to harvest and yield. Johnny’s points out that yield varies widely with technique, conditions, harvest stage and seed lot, so your own records will soon be more useful than any chart.
FAQs
How long do arugula microgreens take?
About 6–14 days from sowing to harvest.
Do arugula seeds need soaking?
No; sow them dry.
How much arugula seed per tray?
About 10 g per 10 x 20 inch (25 x 51 cm) tray.
Can arugula microgreens grow on a windowsill?
Yes; arugula tolerates lower light than most microgreens.
Why are my arugula microgreens bitter?
They were likely harvested late or grown too warm.
Do arugula microgreens regrow?
No; sow a new tray each time.
Sources
- Utah State University Extension — Grow Your Own Microgreens
- Johnny’s Selected Seeds — Micro Greens Yield Trial 2017
- Johnny’s Selected Seeds — Microgreens Comparison Chart
- Virginia Cooperative Extension — Introduction to Microgreen Production
- University of Maryland Extension — Growing Microgreens and Baby Greens Indoors
- Penn State Extension — Growing Microgreens
- Photo credits (Wikimedia Commons, edited with titles): Rucola Fäulnis in Packung-1-JS by Schlaghecken Josef (CC BY-SA 4.0); Lufa Farms Microgreens in Trays by Lufa Farms (CC BY-SA 2.0); Lufa Farms Microgreens in Trays by Lufa Farms (CC BY-SA 2.0); 20160617-AMS-LSC-9000 (61-sec.) (27334710733) by U.S. Department of Agriculture (Public domain); Vegetables in Refrigerator Bin by Alabama Extension (CC0)