- To 1.6m tall, branched above, herbaceous, pubescent, often slightly scabrous, 4-angled.
Stem at a node.
- Opposite, petiolate, lanceolate to lanceolate-oblong or lanceolate-ovate, to +/-3cm broad, +15cm long, serrate to double serrate, scabrous above, pubescent below.
- Multiple terminal spikes, with flowers dense and overlapping, indeterminate.
Single spike of inflorescence.
- Corolla whitish to blue-purple or rose, to 10mm long, 4mm wide at apex, tubular, salverform, 5-lobed, zygomorphic. Stamens 5, included within corolla. Calyx to 3mm long, tubular, pubescent, 5-lobed(toothed).
- June - October.
- Moist ground, waste ground, pastures, thickets, meadows, streambanks, roadsides, railroads.
- Native to U.S.
- This plant is sometimes confused with
but the latter has flowers which are not as dense on the spikes and with corollas which are typically white.
also has much broader leaves than does
is a common plant and can bloom when quite small if mowed or cut frequently.
Steyermark lists three forms for the species. Form
, pictured above, has the typical blue-purple corolla. Form
, has a rose-colored corolla and is rare. Form
, has a white corolla and is also rare.
Photographs taken off Shaw Ave., St. Louis, MO., 7-28-03.