If you don't already have termites, then there are a lot of things you can do to prevent an infestation in the first place.For the most part, home remedies and "natural" ways of dealing with them will ONLY prevent an infestation. If you've already got a colony in or near your home, you're going to have to have a professional get rid of it. You can, however, cut down on chemicals and costs by some simple termite prevention techniques. They aren't foolproof, but they will reduce the chance of another infestation.
Keep moisture away from your house. Termites will head right for your home if the soil near it is moist, so there are a few things you need to do to stop that. First of all, trim and prune plants that are near your house. Clean your gutters, and make sure they drain water at least a little bit away from your foundation. Check any faucets, hoses, or air conditioners - leaks are a common reason for termites being attracted to your house. Termites don't just burrow in wood - they extend the nest into the soil to get moisture. Move your sprinklers so that the spray is at least a couple feet away from your house. Finally, in some cases you have to do some grade work near the house to make sure water flows away from it. That can be important for other problems as well, like mold and other pests.
Get rid of wood debris in your yard or near your home. For termites, wood is food - and a food source near your house means the next thing they're going to eat is your home itself. Firewood, old stumps, newspapers, magazines, cardboard boxes, grading stakes, and scraps of wood or branches should all be removed from anywhere near your house.
Check your house for cracks. Any easy way for termites to get in, especially into the foundation, should be sealed or caulked up.
Wood structures near your house should not touch the ground. Most houses won't be designed with this problem - but many people put decks, latticework, door frames, or stairs on their homes as well. You need about half a foot free space between the ground and any wood.
Use woods that are termite-resistant. Popular ones include redwood, juniper, and cedar - they aren't termite-proof, but they are a less attractive food source for them.
Use sand barriers. Termites cannot tunnel through sand, so it is often used as a way to stop them from entering your home. Termites use their mouths to burrow, and they can only move particles of a certain size. You want sand that can just go through a 16-mesh screen - any bigger or smaller and the termites may be able to get through.
Have your house inspected regularly - at least once a year. Regular inspections will catch colonies before they are fully built - and before they've done much damage to your home.
Do NOT mess with any termite colonies you find on your property. This is actually a pretty common cause of infestation. A homeowner will find a termite colony on their property or nearby - maybe in an old stump or piece of wood. The owner decides to get rid of it themselves, dousing it with bug spray or trying to destroy it. All that happens is the colony will try to move - and it often moves right into your home. If you ever find a colony on your property, you should have it treated professionally. It is very difficult to kill off a colony entirely on your own, because "reproductives," a kind of termite, can turn themselves into queens if needed. They aren't like ants, which have only one queen, and the colony dies if it dies.