Getting it to bloom

Why won't my Cow Parsley bloom? (and how to make it flower)

Also called Cow Parsley, Wild Chervil, Queen Anne's Lace, Keck (Anthriscus sylvestris).

More about cow parsley

About Cow Parsley

Anthriscus sylvestris · also called Cow Parsley, Wild Chervil · flowering

Anthriscus sylvestris is a robust biennial or short-lived perennial native to Europe, western Asia, and northwestern Africa, and one of the most familiar hedgerow and woodland-edge wildflowers in the British Isles. It produces finely divided, fern-like foliage and large flat-topped umbels of tiny white flowers from April to June. The most important care fact is that it self-seeds prolifically and can quickly colonise an area; deadhead before seed sets if spread is unwanted. The plant contains furocoumarins that cause phototoxic skin reactions and is considered mildly to moderately harmful if ingested by cats or dogs.

Plant type: flowering

The reasons cow parsley isn't blooming

Almost every non-blooming cow parsley traces back to one of these, roughly in order of how common they are:

Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
The plant has not been deadheaded, so it stops flowering once it sets seed.
Irregular watering — drought or waterlogging at the budding stage makes buds abort.
It is still too young or was checked by a transplant and is rebuilding before flowering.

Feeding cow parsley a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

The fix — how to get cow parsley to flower

Maximise sun. Give cow parsley the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.

Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for cow parsley and get the feeding right with the cow parsley fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.

Bloom season and what to expect

Cow Parsley flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

Post-bloom care so it flowers again

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

For everything else this plant needs day to day, see the full cow parsley care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Cow Parsley blooming — frequently asked questions

Why won't my cow parsley flower?

Cow Parsley blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.

How do I make cow parsley bloom?

Give cow parsley the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.

When does cow parsley normally bloom?