The overall shapes of canna leaves are characteristic of the genus, and together with reproductive features, are used in plant identification.
To assess the shape of a leaf, one examines the outline formed by the apex, margin, and base of the leaf. Cannas always have smooth margins, i.e. no teeth or lobes along its margin.
There are basically six shapes of canna leaves, although some give us an issue with naming as they fall between two of the six basics. It must also be said that Cannas are so cantankerous that not only are flowers rarely the same exact shape, unlike say the conforming rose family, but the same plant can also grow subtly different leaf shapes within a few weeks of each other.
Acuminate
[From Latin “acuminatus” = pointed] An acuminate leaf is a simple leaf narrowing to a slender point.Mucronate
[From Latin “mucronatus” = cutting edge] Linear leaves that have a long and very narrow leaf shape, with sides that are almost parallel with one another and are usually more than four times longer than broad.Ovoid
[From Latin “ovum” = egg] Ovoid leaves have the same shape as an egg, or of a similar shape.Oblong
[From Latin “oblong” = elongated, oblong] Oblong leaves have a rectangular leaf blade two to four times longer than it is wide, with sides that are almost parallel to each other.Oval
[From Latin “ovum” = egg] Oval canna leaves have a rounded and slightly elongated outline or shape like that of an egg, but longer and not as round as ovoid leaves.Lanceolate
[From Latin “lanceolatus” = shaped like a small lance] Lanceolate leaves are a lance-shaped leaf, with the widest part of the leaf near the base and the narrowest part near the apex.