Methylates caffeoyl-CoA to feruloyl-CoA. Has a very low activity with caffeic acid and esculetin. Involved in scopoletin biosynthesis in roots. (E)-caffeoyl-CoA + S-adenosyl-L-methionine = (E)-feruloyl-CoA + H(+) + S-adenosyl-L-homocysteine Binds 1 divalent metal cation per subunit. Aromatic compound metabolism; phenylpropanoid biosynthesis. A number of isoforms are produced. According to EST sequences. Expressed in stems and roots. Detected in leaves, siliques, flower buds, flowers. Expressed in the tapetum, but not in the endothecium. Detected in the vascular system of leaves and all flower organs, including stigma, stamens, petals and sepals. Expressed in young flower buds and decreases just before the petals appearance. No visible phenotype, but slightly smaller when grown in short days conditions. 70% and 85% reduction in scopoletin and scopolin levels respectively in the roots. Reduction in global lignin content and in hydroxycinnamic acid amides content in pollen. Belongs to the class I-like SAM-binding methyltransferase superfamily. Cation-dependent O-methyltransferase family. CCoAMT subfamily.