IPM1007, Revised November 2009
A perennial with square stems and light blue to purple tube-shaped flowers. Seedlings have cotyledons that are spatula shaped. First true leaves as well as all subsequent leaves have "crinkled" surfaces. Leaves are arranged oppositely along the stem and are oval shaped in outline. Lower leaves occur on petioles while upper leaves may not. Stems are branched and usually grow prostrate along the ground. Stems are distinctly square and hairy when young but usually without hairs on older plants. Stems can root at the nodes. Flowers occur in spikes at the ends of erect stems.
IPM1007, revised November 2009
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