Shepherd's-purse is an introduced weed found across most of North America, especially in fields, gardens, roadsides, and other disturbed ground. Its tiny heart-shaped seedpods make it easier to recognize than its small white flowers do.
Appearance
Growth form
This plant lives for one or two years and usually grows 4–20 in (10–50 cm) tall. Its lower leaves form a before slender flowering stems rise above them.
Leaves
Lower leaves are toothed or deeply divided. The smaller stem leaves have no stalk and clasp the stem.
Flowers
Each tiny white flower has four petals.
Flowering time
In Utah, flowering and seed production can run from April through September. In mild coastal California, flowers may appear at other times too.
Fruit
The flat seedpods are triangular to heart-shaped and contain many small reddish-brown seeds.
Virginia pepperweed has small, nearly round seedpods and usually loses its rosette of lower leaves by flowering time. Shepherd's-purse keeps its unmistakable triangular or heart-shaped pods.
Why they get mixed up · Both have tiny white flowers and flat seedpods on narrow stems.
Field pennycress has much larger, nearly round winged pods with a deep notch at the tip. Shepherd's-purse has smaller pods with a pointed base, like a simple heart.
Why they get mixed up · Both are small white-flowered mustards of disturbed ground.
Where it lives
Typical habitats
fields and gardens
roadsides
disturbed ground
Range
It is widespread through most of North America, from low ground to areas near the tree line. It is not native to the United States.
Preferred conditions
It favors open ground and tolerates many disturbed sites, but it does not thrive in deep shade.
Flowering
Flowers Apr–Sep
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Flowers
Flowers Apr–Sep
Life cycle
Reproduction
It reproduces by seed rather than by spreading stems or roots.
Seed dispersal
The plant makes abundant seed that can be moved by birds and other foraging animals.