How do you grow sorrel microgreens? Scatter sorrel seed densely on a moist mix or grow mat, press it in, and keep it covered near 75°F (24°C) until it sprouts. Then grow it under light at 65–75°F (18–24°C) with bottom watering, and cut at 1/2–2 inches (1–5 cm). Johnny’s Selected Seeds lists sorrel microgreens at 10–15 days.
Key takeaway: Sorrel microgreens bring a bright, lemony tang that few other micros can match. Johnny’s Selected Seeds sells a French-type sorrel (Rumex acetosa) microgreen with oval green leaves and a lemon flavor in its fast-growing 10–15 day group, and University of Minnesota Extension notes that sorrel belongs to the buckwheat family and has a sour flavor.
| Factor | Guideline | Source |
|---|---|---|
| Days to harvest for sorrel microgreens | 10–15 days | Johnny’s Selected Seeds |
| Seed count | About 454,800 seeds per lb | Johnny’s Selected Seeds |
| Germination temperature | 75°F (24°C), then 60°F (16°C) root zone | Johnny’s Selected Seeds |
| Air temperature | 65–75°F (18–24°C) | Johnny’s Selected Seeds |
| Harvest height | 1/2–2 in (1–5 cm) | Johnny’s Selected Seeds |
| Caution | Contains oxalic acid; use sparingly if that is an issue | University of Illinois Extension |
What Do Sorrel Microgreens Taste Like?
Tart and lemony. Johnny’s describes its sorrel microgreens as lemon-flavored with oval-shaped green leaves that add zest to soups, salads and other dishes. University of Illinois Extension says the flavor of French sorrel is very acidic and lemon-like, and University of Minnesota Extension calls the leaves bright and lemony, good in mixed salads, on sandwiches and in soups.
Cooking tames the sourness. University of Minnesota Extension notes that cooking greatly reduces sorrel’s tartness, so sorrel microgreens are best added raw at the end when you want their full citrus bite.
- Look: small, oval, bright green leaves.
- Taste: sour, citrusy and fresh.
- Use: fish, eggs, salads and as a garnish on soups.
How Much Seed Do Sorrel Microgreens Need?
Sow small seed densely. Johnny’s lists about 454,800 sorrel seeds per pound but does not publish a yield-trial rate for this variety. Penn State Extension recommends about 2 seeds per square inch (1 per cm²) for large seeds and up to 12 per square inch (6 per cm²) for small seeds. On a 10×20 inch (51 cm) tray (200 sq in), that is roughly 400–2,400 seeds, or about 0.4–2.4 g of sorrel seed by our math.
Our microgreen seed density guide explains how to fine-tune that range.
How Do You Grow Sorrel Microgreens Step by Step?
Use Johnny’s standard method. Broadcast seed on moist potting mix or another soilless medium in shallow trays, press it firmly for good contact, and cover lightly with mix, vermiculite or a humidity dome. Johnny’s says microgreens can germinate on heat mats, in germination chambers or on benches, and its chart notes that all of its microgreens are suitable for hydroponic growing.
- Fill a shallow tray with moist mix or a grow mat.
- Weigh out untreated sorrel seed for your tray size.
- Spread evenly and press seed into the surface.
- Cover with a thin layer of mix or a blackout lid.
- Keep the root zone near 75°F (24°C) until it sprouts.
- Uncover and move under a grow light.
- Bottom water to keep moisture even.
What Light and Temperature Do Sorrel Microgreens Need?
Moderate warmth and bright light. Johnny’s recommends 75°F (24°C) soil until germination, then 60°F (16°C), with air at 65–75°F (18–24°C), and warns that temperatures above 75°F (24°C) raise disease risk. Oregon State University Extension suggests covering trays for about three to four days, then using a lamp about 3 inches (7.5 cm) above the plants for around 15 hours a day.
- Blackout: about 3–4 days, until most seeds sprout.
- Light: around 15 hours a day; dim light makes leggy greens.
- Airflow: a small fan helps prevent damping-off.
Our microgreens light requirements guide covers fixture choice.
How Do You Water Sorrel Microgreens?
Bottom water and never let the tray dry out. Johnny’s recommends bottom watering or misting so mix does not splash onto the seedlings, and says to maintain even moisture. In potting mix, plain water is usually enough; on hydroponic mats with no nutrients, Johnny’s says a dilute fertilizer solution is appropriate. See our microgreens bottom watering guide.
When Do You Harvest Sorrel Microgreens?
Usually 10 to 15 days after sowing. Johnny’s says to harvest once the cotyledons are fully developed or when the first true leaves begin to emerge, typically at 1/2–2 inches (1–5 cm) tall. Cut with scissors or a sharp knife and minimize handling. Penn State Extension says most microgreens are harvested 7 to 21 days after germination.
Are Sorrel Microgreens Safe to Eat?
Yes, in normal amounts. University of Illinois Extension says sorrel leaves contain oxalic acid, which can be a problem for people with certain health conditions, so use sorrel sparingly if oxalic acid in your diet is an issue. It also notes sorrel’s high acidity may discolor some metal pots. Penn State Extension advises buying untreated seed sold for sprouts and microgreens.
How Long Do Sorrel Microgreens Last?
About 5 to 10 days when stored well. Johnny’s says microgreen shelf life ranges from 5 to 10 days under proper storage conditions and that they must be washed before serving. Oregon State University Extension suggests wrapping greens in a paper towel, sealing them in a plastic bag in the refrigerator, and using them within one to two days for top quality.
Can You Grow Sorrel Past the Microgreen Stage?
Yes. University of Minnesota Extension says sorrel is a perennial vegetable hardy into USDA Zone 3 and suggests starting seed indoors about three weeks before the last spring frost. Spare seedlings can be potted on into full-size plants; our guide on how to grow sorrel hydroponically covers adult plants.
FAQ About Sorrel Microgreens
How long do sorrel microgreens take?
About 10–15 days, per Johnny’s.
What do sorrel microgreens taste like?
Tart, acidic and lemon-like.
Can sorrel microgreens grow hydroponically?
Yes, on grow mats with bottom watering.
Do sorrel microgreens contain oxalic acid?
Yes; use sparingly if that is a concern.
Is sorrel microgreen seed small?
Yes, about 454,800 seeds per pound.
How tall should sorrel microgreens be at harvest?
About 1/2–2 inches (1–5 cm).
Sources
- Johnny’s Selected Seeds — Sorrel Microgreen Seed
- University of Minnesota Extension — Growing Sorrel
- University of Illinois Extension — Sorrel, French
- Penn State Extension — The ABCs of Microgreens
- Oregon State University Extension — Microgreens
- Photo credits (Wikimedia Commons, edited with titles): Rumex acetosa kz09 by Krzysztof Ziarnek, Kenraiz (CC BY-SA 4.0); Rumex acetosa 81031020 by Юлия Медведько (CC BY 4.0); Rumex acetosa kz05 by Krzysztof Ziarnek, Kenraiz (CC BY-SA 4.0)