Wall Speedwell

• Growing form

  Annual herb.

• Height

  5–25 cm (2–10 in.). Stem ascending–erect, hairy.

• Flower

  Corolla almost regular (actinomorphic), pale blue–almost white, 2–3 mm (0.08–0.12 in.) broad, fused, 4-lobed, wheel-shaped, short-tubed. Calyx 4-lobed, with glandular hairs. Stamens 2. Pistil a fused carpel. Inflorescence a long, dense terminal raceme. Flower-stalk shorter than subtending bracts.

• Leaves

  Opposite, lower short-stalked, upper stalkless. Blade triangularly ovate, with blunt or shallow cordate base, margin blunt-toothed, even uppermost leaves not lobed.

• Fruit

  Obcordate capsule, deeply notched, flat, as long as broad, edge with glandular hairs.

• Habitat

  Dry meadows, rocky meadows, field margins, fallow fields, gardens, roadsides, waste ground.

• Flowering time

  May–August.

Wall speedwell’s pale blue flower is small and modest. Its beautiful blue corolla does not show up well in amongst its large subtending bracts, even though the annual is dependent on seed production and therefore pollination. Wall speedwell is apparently self-pollinating and thus has an abundant seed harvest: in one capsule there are close to 20 seeds, and the largest specimens can have more than one hundred capsules. The species’ favoured dry meadows and rocky outcrops are so low-growing that new shoots are not suffocated by bigger plants. In dry habitats the plant flowers at the beginning of spring before the summer heat scorches the thin soil, which is still damp to a certain extent from the winter. The spring weather has a big effect on species that grow in dry areas, and the number of wall speedwell plants correspondingly varies greatly from year to year. The species seems to have arrived in Finland with the beginning of agriculture and begun to grow in yards and on arable land and soil heaps.

A positive identification of the species is usually made by making a closer examination because especially wall speedwell that grows on rocky outcrops is very like spring speedwell (V. verna). The easiest way to identify the plants is from the leaves: wall speedwell’s uppermost leaves are entire, while spring speedwell’s are lobed.