Common Fumitory: How to Recognise It and Why It Is Called That

In brief: Common fumitory (Fumaria officinalis) is an annual weedy herb with grey-green, finely divided leaves and tiny pink flowers, which grows in fields, gardens and fallow land from May to October. It got its name from the bluish, "smoky" tinge of its leaves. In larger quantities it is risky for animals, so it is not advisable to let it overgrow on pastures or in fodder.

Fumitory is one of the plants that most people meet in the garden as a weed, without suspecting that it has its own name and history. The small herb with grey-green tinged leaves and pink-purple flowers used to be among the commonly gathered medicinal herbs; today we meet it mainly in vegetable beds or among root crops, where it competes for space with cultivated plants.

This overview explains how to recognise fumitory, where its name came from, where it grows and how to deal with it if it appears in your garden.

What fumitory looks like and where its name comes from

Common fumitory is an annual herb with a hollow, branched stem 10 to 30 cm long and finely, twice-pinnately divided leaves in an unmistakable grey-green, even bluish shade. It is precisely this leaf colour, which from a distance resembles smoke hovering above the ground, that gave the plant its Czech and Latin names – "fumus" means smoke in Latin. The tiny pink to pale pink flowers with a dark purple tip bloom in racemes from May to October and are pollinated mainly by flying insects.

Where fumitory grows

You will find it in fields among root crops, in gardens, on fallow land and also along paths and in parks. It thrives best on damper, fertile, humus-rich or sandy-loamy soils, which may be slightly acidic to alkaline. As a typical weed it quickly colonises freshly worked, rich soil, and so it often appears just where the soil has recently been dug or fertilised.

Fumitory in the garden: weed or welcome guest?

In vegetable beds fumitory is perceived as a weed, because it quickly forms dense stands and competes with cultivated plants for water and nutrients. On the other hand, it is a plant of the native flora that provides nectar for insects, and in small quantities at the edge of a bed or in a cultivated but not intensively farmed corner of the garden it need not be a problem. If you want to control it, the most effective approach is regular weeding at the young stage, before the plant sets seed and spreads further.

Historical and traditional use

In the past common fumitory was grown and gathered for medicinal purposes and was part of the folk herbal tradition throughout Europe. The herb contains a number of alkaloids and other substances that have been the subject of traditional and modern pharmacological interest. Today, however, self-treatment with fumitory is not recommended – exact dosing for home use is not reliably verified, and the plant is nowadays used mainly in professionally controlled preparations, not as an herb to gather and dry yourself.

Why fumitory is risky for animals

When eaten in larger quantities, fumitory can cause digestive problems and irregular heart activity in animals. The risk applies mainly to the situation where the plant gets in large quantities into fodder or onto a pasture, where animals graze it together with the other vegetation. In an ordinary garden, where fumitory appears singly among vegetables, the risk is not comparable, but it is nevertheless sensible not to let it grow up in masses where pets or farm animals have access.

When and how fumitory spreads most in the garden

Fumitory germinates practically throughout the season as soon as the soil is damp and warm enough, but most strongly in spring after the bed has been worked. Because it is an annual, it can complete its whole life cycle even repeatedly in one season – it germinates, flowers, forms seeds and germinates again, if you do not prevent it. Thanks to this it can multiply quickly in a suitable position and fill a free area of the bed within a few weeks, especially where the soil has stayed bare for a longer time after harvest and unshaded by other vegetation.

Fumitory seeds remain viable in the soil for several years, so the same plant may appear again even after you have apparently weeded it out completely. Regular hoeing and removal of young plants before they set seed is therefore much more effective in the long term than a single thorough and laborious weeding once in the whole season.

Fumitory and neighbouring crops

In a bed of root crops such as potatoes or carrots, fumitory is one of the most common accompanying weeds, because the same freshly loosened and rich soil suits it. Unlike creeping thistle or cleavers, however, it does not spread by underground runners, so it can be removed mechanically fairly easily, as long as it is not given time to go to seed. To a lesser extent it is also part of more species-rich, extensively cultivated beds, where it serves as a source of nectar for small insects.

How to tell fumitory from similar plants

The most reliable feature of fumitory is precisely that bluish, "smoky" colour of the finely divided leaves in combination with tiny pink flowers – none of the common weed plants in the garden has this combination.

Frequently asked questions

Is fumitory poisonous to humans?

In larger quantities the alkaloids it contains can cause digestive problems, but ordinary contact while weeding is not dangerous. Internal use without expert guidance is not recommended.

What is the best way to get rid of fumitory in a bed?

The most effective is regular weeding of young plants before they form seeds, because an annual weed spreads mainly by seed. Mulching bare soil will limit its further germination.

Why is the plant called fumitory?

Because of the grey-green to bluish colour of the finely divided leaves, which from a distance resembles smoke rising from the ground.

Can fumitory harm pets or farm animals?

In larger quantities yes, it can cause digestive problems and irregular heart activity. Do not let it grow up in masses in places where animals have access to graze.

Can fumitory be put to use in the garden, or is it just a nuisance?

In smaller quantities it provides nectar for insects and is part of the natural garden flora. As a weed in a vegetable bed, however, it competes with cultivated plants for water and nutrients, so it is usually controlled.

Does fumitory also grow in a lawn?

In an ordinary, regularly mown lawn it does not establish itself much, because frequent mowing does not let it flower and set seed. It appears rather in unmown edges, in beds, among root crops and around the compost heap.

Sources

• Wikipedia – Common fumitory (Fumaria officinalis)
• Toxicological Information Centre (TIS) – information on risky plants

Updated: 10 October 2026