When my Grandson was 3, he wanted to grow a garden, but he had a problem with his 2 big dogs, and knew if he had the garden too low to the ground they would dig it up.

So I built him a 2' x 8' Sub-Irrigated Planter. I, installed it on 3 stacked concrete blocks and anchored it to the fence posts.

Yes, he knew he would have to get a 3 step stool to plant and harvest, but the dogs never got into it.

8" deep soil-less media, and a 6" deep water reservoir holding 60 gals. of water.

I had trouble with cats using my beds as litter boxes. I bought the cheaply wire flower bed borders. They are about a foot plus tall and hinged together. I zig zagged them in my beds so they didn't leave much room for even an agile cat to maneuver. The plants grow right up beside them. Hope that makes sense. Dogs would also get tangled up in them. Now would be a good time to put them into a bed when nothing is growing in the beds. Even if the dogs knock them over they will still tangle up their feet.

Wonderful idea with the sub-irrigated planter! It also worked well for me considering that I live in an apartment with not a lot of gardening space. :)

I think if you use a creative container like a basket or bicycle you can come up with some really fun ideas of gardening. I think that having them in containers rather than just the ground around you will make it more accessible and easier to take care of. There were are a lot of fun ways to decorate your townhome garden. http://containercreationsplus.com/do-it-yourself.html 

What about something like this? http://verticalgardeningsystems.com/Item/mobilegro3tier  I really like these. If that's above your budget, there are some other ideas there too.