Only the type variety is known from Victoria. See description under Opuntia engelmannii var. engelmannii.
Opuntia engelmannii is a very polymorphic species with many described varieties. Additionally, it also hybridises with O. stricta, O. phaeacantha Engelm. and O. littoralis (Engelm.) Cockerell in the USA (Pinkava 2003), thus blurring the species boundaries. O. e. var. linguiformis Griffiths) B. D. Parfitt & Pinkava is naturalised in South Australia, and there are reports from Victoria, but there are no specimens to substantiate the presence of the taxon in Victoria. This variety is distinguished by its more elongate cladodes (45–120 cm long, 10–17 cm wide).