Heliotrope , (heliotropium, Linn.), the name of annual or perennial plants belonging to the natural order boraginacece. H. curassavicum is a smooth annual found in Virginia, Illinois, and southward. H.Europoeum occurs sparingly in the southern states as an introduced weed. The species in cultivation are H. Peruvianum and H. corymbosum; these have woody stems, oblong hairy leaves of a pale green color, and terminal, branching flower stalks. The pleasantly fragrant flowers are small, but they grow compactly in the recurved spikes. The corolla is intersected at its mouth with five folds, and is of a purple-lilac color, with a greenish white throat. The principal difference between the two species is that the last named has larger, darker colored, and less strongly scented flowers. Numerous seedling varieties have been raised, chiefly distinguished by the tint of the corolla, a yellowish or pure white throat, or else by the greater size of the spikes or "trusses." Heliotropes are readily propagated from cuttings of tender shoots, and great numbers are raised annually by florists for sale as bedding plants; though it is a shrub, small plants from the unripe wood will flower freely.
Plants for the greenhouse may be trained as standards or pyramids, or they may be trained to the wall of a greenhouse; thus treated they will grow 4 or 5 ft. high. The odor of the heliotrope is compared by some to that of vanilla; in England it is frequently called "cherry pie" on account of its fragrance. Pliny and Dioscorides assert that the flowers of the heliotrope turn toward the sun, whence its ancient and generic name. For the same reason it has also been called turnsole and girasole. - False heliotrope (Tournefortia heliotropioides) is a garden annual, with flowers closely resembling those of the heliotrope in everything except odor; the plant when bruised is disagreeably scented; in some southern gardens where it has been raised for ornament it has established itself as a weed. Indian heliotrope (heliophytum Indicum) is a coarse hairy annual with much the aspect of a heliotrope, which has been introduced from India, and is found in waste places in Illinois and southward.