Veronica anagallis-aquatica / blue water speedwell

Adjectives: , , , ,

  • small blue to mauve or lavender flowers; 4 petals
  • many flowers per stalk, but only a few blooming at once
  • opposite leaves tightly clasping the stems
  • in standing water or slowly moving streams

Synonyms: many!
Also known as: brook pimpernel, sessile water speedwell, water speedwell


Perhaps the hardest thing about discussing this species is defining the flower color. They can be white, which is easy. More likely they are some kind of blue, or pink-lavender or purple, depending in part on the plant and in part on the color perceptions of the describers. In any case, they commonly have purple lines running from the center to the ends of the petals. The individual flowers are also quite small, ca. 1/4 inch across, and have 4 petals.

More notable, however, is the flower arrangement. They appear on axillary racemes, meaning that they branch off the main stem of the plant at a leaf-stem junction. Individual racemes may have over 30 flowers, but only a few flowers are in bloom at one time.

The leaves themselves are opposite and sessile, perhaps clasping (shown well in the gallery photo), and may be up to 4 inches long. Both of these characteristics distinguish this species from other speedwells.

Most distinguishing, however, is the fact that this is an aquatic plant, found at least in consistently wet conditions, but most distinctively in slow streams and springs. There, water speedwell is an herbaceous perennial with a fibrous root system, spreading by seed or by rhizomes or stolons. The stems are relatively thick, growing upwards or sideways, curving upward only at the end (decumbent). This is also pretty clear in one of the gallery photos. In that case, the plants take root from the leaf nodes where they touch the soil or mud.

It is not completely clear whether water speedwell is native or introduced. Except for a few states in the southeast US, it is found in all other states. It doesn’t seem to be a pest or weed anywhere, certainly not in the Valley.