Shepherd's purse

Shepherd’s purse (Capsella bursa-pastoris) is a persistent weed that is found across much of the world as well as Great Britain. It grows on wasteland and also in gardens and on farmland.

It grows to 18 inches (45 centimetres) in height and also sprawls across the ground. The stems can be either branched or unbranched. The lower leaves, which form a rosette, are dull green in colour and are lobed to a greater or lesser extent. The upper leaves clasp the stem.

The small white flowers, which can appear at any time of the year, form in clusters at the tip of the stem.

The seed-pods have a distinctive heart shape, or a triangle with a notch at the top. This is the feature that gave the plant its name, because it was noted centuries ago that shepherds took their lunch into the fields in a pouch that was just this shape, slung from a belt. The resemblance to a coin purse is reinforced by the fact that, when ripe, the seeds will spill out of the pod if it is touched, just like coins from a purse.

An alternative name is “mother’s heart”, because of a trick that children would play on each other. An unwitting child would be asked to pick the ripe heart-shaped pods from a shepherd’s purse plant and, when the inevitable happened, would be told that he or she had just broken his or her mother’s heart!

Although insects do visit shepherd’s purse flowers, many plants self-pollinate. This leads to local inbreeding and variations in the appearance of the plant as between different colonies.

© John Welford