Insects are a big problem with any garden, but don’t forget the bigger pests. All sorts of animals are going to look at your garden like it’s a spread out buffet, and they can quickly do a lot of damage because of their larger size.
A fence is a possibility, though many common garden pests will just hop or climb over it. A four-foot fence would keep out most rabbits, but squirrels or racoons would just climb over. It would also keep out any roaming cats and dogs that might be happy to dig around and make a mess (it’s unlikely they would eat anything). For deer, it would need to be at least 8 feet high.
You can kick it up a notch with electrical fencing if you really need to keep the animals out. Even just two or three lines of wire can be enough. One shock and most animals (even stubborn racoons) will be deterred. It’s a little more technical than a standard chicken wire fence, and the cost will be a bit higher too. You can get the materials at large gardening or farm supply stores. Ask the staff for some tips on putting it all together.
Is fencing impractical for your garden? You do have other options. Animals use their sense of smell much more than we do, and you can repel many animals by adding a few less appealing scents to your garden. Garlic cloves, slivers of scented soap, puree of hot pepper, mothballs or even predator animal urine (you can buy this last one) can all work to make your garden less interesting to animals. You’ll have to reapply many of these scents after a rain though.
What about underground pests? Gophers, ground hogs or voles can chew through a lot of roots and you will never see a thing. Obviously, typical fences won’t help. With a bit more effort, you can install a barrier of underground fencing at least two feet down to block most burrowing animals. Just dig a ditch around the garden, add fencing material and then refill. Scent repellents can be a bit of a help if you can find some access to their tunnels. Otherwise, you may have to resort to poisoning or traps.
Not all animal pests are the four-legged kind either. Birds can be a real problem with some crops, particularly berries or any patch with new seeds in the ground. A sheet or two of light bird netting over your plants should keep them out.