'constant-flowering' originates from Modern English, specifically the compound of 'constant' and 'flowering', where 'constant' ultimately comes from Latin 'constans' (meaning 'standing firm, steadfast') and 'flowering' derives from Old English 'flōwer' via Middle English 'flour/flower' (meaning 'blossom').

'constant' passed into English from Latin (via Old French/Middle English) as 'constans' → 'constant'; 'flower' developed from Old English 'flōwer' and Middle English 'flour/flower', with the gerund/participle form becoming 'flowering'; the compound 'constant-flowering' is a modern English formation used in horticultural description.

Initially the elements meant 'steadfast/unchanging' ('constant') and 'blossom' ('flower'); when combined in Modern English the compound came to mean 'producing blossoms continuously or repeatedly', a specialized horticultural sense.