Disclosed is an agrochemical delivery unit comprising an impermeable cell which is a cell made of material that is impermeable to water; an agrochemical within the impermeable cell; and a wick comprising a hydrogel, said wick having a portion located within the impermeable cell and a portion located outside of the impermeable cell. Also disclosed is an agrochemical delivery unit comprising (a) a cell comprising two or more cell wall segments wherein at least one segment is impermeable to water and at least one segment is permeable to water; and (ii) an agrochemical within the cell. The invention provides methods of making and using the units.