Cow parsley

How to recognise it

Growth habit

Perennial with a taproot; hollow flowering stems of 60–150 cm.

Leaf

Two to three times pinnate, finely cut and fern-like, fresh green and slightly hairy; appears as early as late autumn or winter.

Flower

Small white flowers in loose umbels of 4–8 cm; the outer flowers of each small umbel are slightly larger. From April to June.

Stem

Hollow, grooved, hairy below and hairless above; green, sometimes flushed purple, but never purple-spotted.

Fruit/seed

Elongated, smooth, glossy black-brown fruits of 6–10 mm with a short beak.

Confusion with

Hemlock (highly poisonous) has a hairless stem with purple blotches and smells of mice; rough chervil has hairy, purple-spotted stems swollen below the joints and flowers later; fool’s parsley has long, downward-hanging bracteoles under the small umbels.

Flowering: April–June · Pruning: June–July

Why grow it?

• One of the first large umbellifers of the year: in April–May an important food source for hoverflies, beetles, flies and solitary bees.
• Creates an airy white haze in a natural garden or along a hedge.
• The fresh young leaves appear as early as winter, bringing green to a bare hedge bottom.
• Hollow stems left standing give shelter to insects.
• A good indicator: where cow parsley grows in masses, the soil is rich.

Cow parsley: where does it grow best?

• In the wild: verges, dykes, hedges, woodland edges, banks and rough ground, especially on rich soil.
• Sun to part shade; under a hedge or a light tree it does very well.
• Normal, fertile soil: loam, clay or humus-rich sand.
• In the garden, best in a spot that is not mown every week: along a hedge, in a rough strip or in an orchard.

Goes well with

• Red campion: Pink flowers among the white lace, in the same hedge bottom.
• Meadow buttercup: Yellow accents in flowering grassland in May.
• Hawthorn: A hedge in flower in May with a white skirt of cow parsley.
• Garlic mustard: Another woodland-edge flower, and food plant of the orange-tip.

Cow parsley: when and how to plant it?

1. Usually cow parsley turns up by itself. If you do want to sow it, buy seed of wild origin.
2. Sow fresh seed in July–October where it is to grow or in pots left outdoors: the seed needs a winter to germinate.
3. The seedlings appear in early spring; most only flower in their second year.
4. Move young plants early and with a good root ball, as they have a taproot; set them 40–50 cm apart.
5. Watering is only needed in the first spring during dry spells.
6. Never dig up plants from the wild, and never pick umbellifers to eat unless you are absolutely sure of the identification.

Care

Water

Not needed once the plant is established.

Feeding

Do not feed. In rich soil cow parsley soon crowds out other flowers.

Mowing

Mow after the seed has set, in late June or July, and remove the cuttings. To reduce it, mow in early June, before the seed ripens.

Spreading

Cow parsley self-seeds heavily. Cut off some of the umbels after flowering.

Making soil poorer

Years of mowing and removing the cuttings make the soil poorer; cow parsley then makes way for more kinds of flowers.

Tip: For more kinds of flowers in a verge or meadow, mow the cow parsley every year in late June and remove the cuttings: after a few years other flowers get more of a chance.

Pruning and mowing

Pruning months: June–July.

When: Late June–July, after flowering and seed set.

How:

• Mow or cut the faded stems close to the ground and remove them.
• Leave a few hollow stems standing or stack them in a pile as shelter for insects.
• After mowing the plant often regrows with fresh leaves that stay green into winter.
• For fewer seedlings, cut off the umbels as soon as they have finished flowering, before the seed turns black.

Caution: Wear gloves when mowing if there may be hogweed among the plants: its sap causes blisters in sunlight.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

Sow fresh seed outdoors in summer or autumn; it germinates after the winter.

Self-seeding

Self-seeds freely. Move young plants as early as possible, with their root ball, because of the taproot.

Cow parsley: how does it get through the winter?

Hardy to −30 °C.

• After mowing, a new green leaf rosette appears in autumn and often stays green all winter.
• Fully hardy, to about −30 °C.
• Dead stems left standing provide hollows for overwintering insects.

Diseases and pests

• Too many seedlings: On rich soil it swamps other flowers. Mow before seed set and remove the cuttings.
• Poisonous look-alikes: Hemlock and fool’s parsley look very like cow parsley. Learn the differences and do not pick it to eat.
• Aphids: May sit on the stems; ladybirds and hoverfly larvae deal with them.
• Powdery mildew: White powder on the leaves after flowering; simply mow the plant down.

Through the year

• January: Fresh green leaves at ground level.
• March: Leaves grow fast; flowering stems come up.
• April: Flowering begins.
• May: Full flower: verges turn white. Lots of hoverflies and beetles.
• June: Last flowers; the seed ripens and turns black. Mow in late June.
• July: Mow and remove the cuttings. Sow fresh seed.
• September: New leaf rosettes. Sow.
• October: Sow in pots that overwinter outdoors.

Did you know?

• The Dutch name fluitenkruid, whistle herb, comes from the hollow stems that children once made into whistles.
• In England the plant is also called Queen Anne’s lace, after the fine white lace of its umbels.
• Garden chervil, the well-known kitchen herb, is a close relative: Anthriscus cerefolium.