Abstract: Various exemplary aspects are directed to mineral wool plant substrates comprising mineral wool fibers bound by a binder formed from an aqueous binder composition comprising a cross-linking agent comprising at least two carboxylic acid groups; a polyol component having at least two hydroxyl groups; a nitrogen-based protective agent; and from 0.05 wt. % to 0.7 wt. % of a non-ionic surfactant. Methods of manufacturing such fiber-based plant substrates can include collecting a plurality of inorganic fibers on a substrate; applying an aqueous binder composition to the collection of inorganic fibers, forming binder-coated inorganic fibers; and curing the aqueous binder composition at a temperature less than 510° F., thereby forming a fiber-based plant substrate, wherein said aqueous binder composition is free of formaldehyde.