Sorrel
Rumex acetosa
Sharp lemony perennial leaf — an easy, shade-tolerant edge to the bed.
- Type
- Herb · Perennial
- Botanical family
- Mixed / other
- Foliage color
- Green
- Sunlight
- Full sun to part shade
- Watering
- Moderate
- Soil
- Moist, fertile
- Feeding
- A compost mulch in spring is plenty; it is a light feeder.
- USDA zones
- 4a–8b
- Frost tolerant
- Yes
- Flowering
- June
- Pruning
- Take off the flower stems as they rise, so the plant keeps making leaves.
- Sow indoors
- 21 days before the last spring frost
- Sow direct
- 7 days before the last spring frost
- Plant out
- at the last spring frost
- First harvest
- 45 days after the last spring frost
- Harvest ends
- 14 days after the first fall frost
- Mar–Mar Spring Growth
- Mar–Jun Harvest
- Jun–Oct Flowering
- Oct–Dec Growing
- Jan–Mar Growing
- Plant spacing
- 11.8 in
- In-row spacing
- 9.8 in
- Between rows
- 15.7 in
- Square-foot density
- 1 per square
- Root system
- A deep taproot
- Working depth
- 3–6 ft
- Can reach
- 10 ft down where the soil allows
- Spread
- 9–15 in across, about 0.75–1.25× the width of the plant
- Shallowest pot
- 24 in of soil
It mines water and minerals from below anything growing around it, which is what makes it drought-proof and what makes it so hard to be rid of: most of these regrow from any length of root left in the ground.
The habit is Sorrel’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.
- Cats and dogs
- Recorded toxic
Recorded as toxic to cats and dogs by ASPCA.
The ASPCA Dock row is printed Rumex sp., a genus row for our genus, carries Sorrel among its own additional common names, and reads Toxic to Dogs, Toxic to Cats, Toxic to Horses. The row is genus-level, which may warn but never clear, and it warns here. The ASPCA's own Sorrel row is Rumex scutatus, a different species. Cornell's Dock row is a Rumex genus row but names only cattle and sheep. The Pet Poison Helpline A to Z index carries no Rumex row.
- When
- One of the first harvests of the year — pick from early–mid spring when the new leaves reach 8–12cm, and again in autumn; summer leaves turn coarse and harshly acidic, especially once the plant flowers. Morning-picked leaves are crispest.
- What to look for
- Young, tender, bright-green arrow-shaped leaves with a clean lemony tang when nibbled. Large, dark, thick leaves and a rising flower spike signal the bitter, oxalic-heavy stage.
- How to harvest
- Cut or twist off outer leaves at the base, leaving the central crown intact, or shear a whole clump 5cm above ground for a full flush of regrowth. Remove flower stalks on sight to keep the plant in leaf production.
- How often
- Cut-and-come-again from spring to autumn — a sheared clump refills in 2–3 weeks. Persistent removal of flower stems keeps leaves tender all season, and the hardy perennial clump returns for many years (divide every 3–4).
- Storing the crop
- Leaves keep 2–3 days in a bag in the fridge but wilt fast. Sorrel doesn't dry, and freezing turns it to mush — the traditional preserve is to cook it down into a purée (it melts almost instantly in butter) and freeze that in portions for soups and sauces.
- Leaf miners Larvae that tunnel pale wandering trails or blotches inside the leaf itself. Pick off and destroy mined leaves; damage is usually cosmetic.
- Slugs & snails Slugs
- Rust Orange-brown powdery pustules on leaf undersides, weakening the plant over the season. Remove affected leaves, avoid overhead watering, and clear all debris in autumn.
Beneficial predators that hunt this plant's pests — grow their favourite flowers nearby to recruit them. companion plant
- Beneficial nematodes Steinernema & Heterorhabditis spp.Hunts Slugs & snails
Microscopic worms watered onto damp soil that hunt down soil-dwelling grubs and release a bacterium that kills them within days. Timing is the whole thing: warm, damp soil and a small target grub, which means late summer for most of what they are used against.
- Centipedes ChilopodaHunts Slugs & snails
Flat, fast, one pair of legs to a segment — and a predator, unlike the slow round millipede it is constantly confused with. It hunts slugs, cutworms, springtails and woodlice by night under mulch and stones. Learn the difference and leave this one alone.
- Frogs & toads AnuraHunts Slugs & snails
A resident toad works the beds every night for slugs, cutworms, and weevils. Recruit them with water — even a sunken basin pond — plus damp shade and an upturned-pot toad house; skip the slug pellets that poison their prey.
- Garden birds PasseriformesHunts Slugs & snails
Both things are true: birds strip your currants and a brood of blue tits takes several thousand caterpillars out of one fruit tree in a fortnight. Net what you must and welcome them everywhere else — a nest box near the apples is worth more than a spray.
- Ground beetle CarabidaeHunts Slugs & snails
Fast, glossy night hunters that patrol the soil surface for slugs, cutworms, and root-fly larvae. Give them daytime cover — thick perennial edges, stepping stones, a log — and skip the tillage that wrecks their burrows.
- Hedgehog Erinaceus europaeusHunts Slugs & snails
A European animal, and worth saying so plainly: there are no hedgehogs in North America, and the ally that does the same night shift here is the toad, the opossum or the ground beetle. Where they do occur, cut a gap in the fence and skip the pellets.
- Parasitic wasps Braconidae & TrichogrammaHunts Leaf miners
Tiny, stingless wasps that lay eggs in or on caterpillars, aphids, and moth eggs — the white cocoons riding a hornworm are their calling card, so leave that caterpillar be. Umbel flowers with shallow nectar keep the adults fuelled.
- Rove beetle StaphylinidaeHunts Slugs & snails
Slim, quick beetles with short wing cases that hunt in soil and litter, taking root-fly eggs and larvae, fungus-gnat larvae, and mites. Mulch and undisturbed ground keep them resident year-round.
- Salamanders & newts CaudataHunts Slugs & snails
Damp-loving hunters of slugs, worms, woodlice and beetle larvae that spend the day under a log or a stone and work the beds at night. Companions to the toads: they want the same damp shade, the same log pile, and the same absence of slug pellets.
- Snakes & lizards Colubridae & PhrynosomatidaeHunts Slugs & snails
A garter snake works the beds for slugs and voles and a fence lizard clears grasshoppers off a sunny wall. Almost every snake a gardener meets is harmless and useful; give them a log pile, a warm flat stone and a bit of cover and they stay.
Strawberries, Lettuce, Cabbage
Good neighbors
Sorrel's sharp lemony tang comes from oxalic acid — the same compound found in rhubarb leaves.
The Cottage Garden Companion — the gardener's herbarium at cottagegardencompanion.com