Drain the excess water to get rid of the larvae. When you water the plants don’t leave excess water behind, as their roots can rot. Or if they are plants that actually live in water, there are two options:

1. Add a couple of goldfish to the water, they will love the larvae as extra food. (You will still need to feed the goldfish normally as the larvae will not be sufficient.)
2. Put a few drops of kerosene on top of the water, it won’t harm the plants but will not allow the larvae to come to the surface and breathe.

But don’t try both things at once as the kerosene would harm / kill the goldfish.