How to Grow Rumex Plants

Gardener's HQ Guide to Growing Sorrel, Dock weed

Rumex are hardy perennial herbs that range from 45 to 60 cm in height.

They have green arrow shaped leaves that can be used in soups, and come into bloom in the middle of summer.

Common names for Rumex genus members is Sheep's Sorrel, Sour weed, and Field sorrel

If growing for culinary use it is recommended that you use Rumex scutatus (French Sorrel).

Rumex venosus
Rumex venosus by Matt Lavin.

Rumex Growing and Care Guide

Common Names: Sorrel, Dock weed.
Life Cycle: Hardy perennial. Some annuals and biennials.
Height: 18 to 40 inches (45—100 cm).
Native: Northern hemisphere.
Growing Region: Zones 5 to 9.
Flowers: Middle of summer.
Flower Details: Pink. Small. Clustered. Unisexual.
Fruit: Small triangular achene.
Foliage: Herbaceous. Dark-green. Large. Ovate with basal leaf lobes, thus producing an arrow shape. Sour/acidic tasting.
Sow Outside: Seeds: 1/4 inch (6 mm). Second half of spring.
Sow Inside: Germination time: one to two weeks. Temperature: ~68°F (20°C). One month in advance. Transplant outdoors following the last frost. Space at 12 inches (30 cm), or grow larger species singly.
Requirements and care: Full sunlight for best results or partial shade. Rich, moist soil. Acidic soil pH 5.5—6. Provide a spring feed. Regular watering to prevent bitter leaves in hot climates. Harvest leaves to promote further growth. Propagate: by dividing at the start of spring or in autumn. Self-seeds readily (Dead-head to prevent seed-set) and can also spread from its roots.
Family:
Closely Related Species:
Miscellaneous: Large genus of 200 species containing both useful plants grown for their edible leaves in soups and sauces (e.g., Common Sorrel: Rumex acetosa), and to wrap butter (Butter Dock: (Rumex obtusifolius) and all out weeds such as Dock. If you are planning to grow this species then you should be aware that it could spread like crazy via its long tap-root system. Therefore, it is highly recommended to grow within a contained space or container. Attracts certain butterflies and moths e.g., the blood-vein moth.

How to Grow Sorrel and other Rumex

Due to their fecund nature it is best to grow Sorrel in containers to separate them from other members of the herb garden. The Sorrel seeds should be sown at a depth of 6 mm in the middle of spring.

The container that Rumex grows in should have a rich acidic soil (pH 5.5 to 6) that is moist, and the container should be placed into a sunny area of the garden. The Sorrel plants should be spaced about 30 to 40 cm apart if using a very large container or singularly in smaller containers.

If starting off indoors then sow sorrel seeds about a month before the last frost. They should take about 9 or 10 days to germinate at 18 to 20 degrees centigrade. Transplant them outdoors just after the last frost.

Caring for Rumex

Easy to look after but difficult to control due to their prolific seed production. In the spring time supply Rumex plants with a feed and a mulch. It is best to water regularly as this prevents the sorrel leaves from having a bitter taste. After three years replace sorrel plants as they tend to lose both vigor and flavor.