Dahlia spectabilis

D. spectabilis is an herbaceous perennial from tubers, with one or more stems that can reach a height of 2.4 m (7.9’). Stems are glaucous and nearly round to slightly angled. Median leaves are 27-35 cm (10.6-13.8”) long (including petioles), twice compound, and frequently with stipels at the first (lowest) and/or second rachis node; blade margin teeth are glabrous (vs. ciliolate). The flower head is up to 14.5 cm (5.7”) across, which is the largest of any species in the genus except D. campanulat. The disc florets of D. spectabilis are yellow and fertile; the 7-8 ray florets are sterile, 5.8-7 cm (2.3-2.8”) long x 2.1-3.2 cm (0.8-1.3”) wide, and light lavender with darker colored longitudinal veins on the abaxial (lower) surface. Flowering occurs from August through at least October (Saar et al., 2002).
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