No, if you're using it by itself as a noun, it's 2nd declension when masculine and 1st declension when feminine, just like most nouns coming from adjectives and exhibiting obvious gender. Agricola and its cousins are exceptions, not the general case. Compare amicus / amica.

Alternatively, if you're using it by itself as an adjective, obviously it will take the appropriate gender. You don't need an explicit noun if you're happy with an implicit "man", "woman", or "thing".