Termites don't eat live plants.

Please post pictures so that we can help you determine what is running amok in your garden.

Post images of the critters and of the plant damage please.

Termites eat cellulose, most often that which is found in woody materials. Termites are needed to digest the fallen trees in the forest, but not the felled trees we build our houses of. So termites are not the problem in your garden, something else is.
Ants are part of Ma Natures recycling machine and will work on most anything they determine to be waste. So even though you have ants in your garden they are not, really, a problem.
Squash bugs, Squash Vine Borer, Cucumber Beetles, etc. can be real problems in any garden and the best defense is a good offense. Floating Row Covers an help as can encouraging beneficial or predator insects to hang around. Most all insecticides will kill off these beneficial/predators as well as the insect pests, however.
This link to an ATTRA publication may be of soem help.

Here is a link that might be useful: organic control of squash pests