Usually, aquatic herbicides are sprayed directly over the top of the lily pad until the surface is thoroughly and evenly coated. Rake away the dead lily pads. The herbicide will kill the plant, leaving dead plant matter floating on the surface. Wade or row into the water and rake away dead lily pads.Click to see full answer. Keeping this in view, does Roundup kill lily pads?A common glyphosate (Roundup) spray should work on lily pads, w/o harming the aquatic life. Might need a surfactant to ensure the spray stays on the leaves. May have a nasty mess when the lily pads die, so raking may be helpful/needed. Roundup is not an approved aquatic herbicide. will grass carp eat lily pads? As such, using fish is best suited for simply controlling native lily pads. Koi, goldfish, and grass carp are all known to eat the leaves and occasionally the roots of water lilies. Of these, grass carp are considered the most effective at controlling lily pad populations. In this manner, can you cut back lily pads? Miniature and dwarf waterlilies will not need dividing or pruning like the larger pond waterlilies. But these smaller waterlilies will benefit from a feed ball now so that they get the nutrient to flower well this Summer.How do you stop lily pads from growing?Control is best achieved through killing of the root system by application of herbicide to the leaves above the water. Cutting water lilies under the waterline 2 or 3 times to drown them can actually stimulate growth. Pulling them out by the roots can be impractical.