A liquid applicator (10, 10A, 10B, 10C, 10D, 10E, 10F) having (i) a container in the form of a collapsible bladder (11, 11A, 11B, 11C) for containing a supply of liquid in use (ii) a positive displacement pump (12, 12A) in flow communication with the container (11, 11A, 11B, 11C) which has a variable capacity chamber for delivering a metered or measured quantity of liquid and (Hi) a contact device (20, 46A, 46A, 60) in flow communication with the positive displacement pump (12, 12A) wherein the metered or measured dosage of liquid is delivered to a plant or other substrate.
