Sorrel is a leafy green vegetable, grown for its pleasantly tart, lemon flavor. It sometimes gets classified as an herb and sometimes as a vegetable. Either way, we don't grow enough of it. Sorrel plants prefer the cool seasons of spring and fall, quickly bolting to seed as the weather heats up. The 2 most commonly grown species are Garden Sorrel (Rumex acestosa) and French Sorrel (Rumex scutatus).
Sorrel plants have smooth, arrow-shaped leaves that grow from a center rosette. The plant will send up a tall flower stalk as the temperature warms. The red flowers are rather insignificant whorled spikes, like rhubarb. Sorrel plants are dioecious.
Sorrel only gets about 12 - 18 inches tall, although the flower stalks will get taller. It does spread out though, easily taking up 2 ft. in width.
Sorrel plants are reliably perennial in USDA hardiness zones 5 and higher, however many people grow them as annuals, starting new plants each spring. Older plants can become tough and less flavorful. Growers recommend either frequent division or sowing new plants each spring.
Plants will grow best in full sun, although a little partial shade will keep them going longer into summer.
Sorrel Growing Tips
Choose a spot with good drainage. Sorrel likes a slightly acidic soil pH; somewhere in the range of 5.5 to 6.8. Since it is grown for its leaves, a soil rich in organic matter will give you lots of leafy, green growth.
You can start sorrel from seed, cuttings, root division, or transplant, in either spring or early fall. Seed can be started indoors or out, but since you can direct sow as early as 2-3 weeks before your last spring frost date, it is easiest to simply sow in the garden. Established plants can handle a light frost.
Sow the seed 1/2 in. deep spaced about 3 in. apart. When the plants are an inch or two tall, thin to a 12 - 15 in. spacing. You should only need 2 or 3 plants, for the average family's need.
Sorrel is an excellent choice for container growing. You should use at least a 6-inch pot, but 8 - 12 inches would be ideal. You can probably keep your sorrel growing longer in containers than in the ground because you can move it out of the sun on warm days.
Caring for Sorrel Plants
Give your sorrel plants regular water; at least 1 in. per week. Mulching will help conserve moisture and keep the leaves clean.
Unless you want to save seed, cut the seed stalk to the ground and remove any declining leaves. The plant should re-sprout with more tender leaves. Sorrel will self-seed if you leave the seed heads on the plants.
To keep your plants healthy and vigorous, divide them in spring or early summer every 3-4 years.
When to Harvest Sorrel
Newly seeded plants take 35 to 40 days to reach "baby" size and 2 months to fully mature. Sorrel is ready to harvest when the leaves are about 4 inches long. Tender leaves are best for eating and if you harvest as cut-and-come-again, you will have a steady supply of young, tender leaves.
Pests and Problems
Sorrel is not often bothered by pests, but aphids may settle in. Blast them off with water and thin the plants, to make them less attractive as hiding spots. You should not have any disease problems with your sorrel.
Suggested Sorrel Varieties
There aren't many seeds or plants with named varieties. They are usually just sorrel, garden sorrel, or French sorrel. French sorrel has smaller leaves and a more subtle flavor.
Richters Herbs introduced 'Profusion' sorrel. It does not set seed and is only grown from divisions, so you will have to purchase or be given your first plant. But it has a distinct advantage, namely wider leaves, that remain tender and non-bitter longer into the season.
There are also 4 more relatives in the Rumex genus that are edible.
- Common or Sheep sorrel (Rumex acetosella) - Although often considered a weed, it is edible and the small leaves are not bad tasting when they are young and tender.
- Red-veined sorrel (Rumex sanguineus) - Does indeed have red veins. It is more ornamental than flavorful, with little of the tartness you'd expect from a sorrel. It does make a nice salad green, though.
- Spinach dock (also known as Patience dock, Garden patience, or Herb patience) (Rumex patientia) - Much taller, at about 4 - 5 ft. in height, with a flavor similar to garden sorrel, however, it is not often cultivated.
- Spinach rhubarb (Rumex abyssinicus) - A giant 8 ft. plant with leaves that can substitute for spinach and ribs like rhubarb.
You can use sorrel fresh, in salads or on sandwiches and you can also cook with it. The leaves tend to dissolve with long cooking, imparting their lemony flavor.
Fresh sorrel does not store well. It will keep in the refrigerator for a week or so, but the flavor and texture will decline. You can freeze or dry the leaves, as you would for any other herb, but the flavor will not match fresh leaves.
Like spinach and rhubarb, sorrel leaves contain oxalic acid, which can be toxic in large quantities. Small amounts will not harm you unless you are extremely sensitive to oxalic acid.