When people think of saving money around the house, they think of things that happen inside, such as utility usage and family meals. But your lawn care and gardening habits could be costing you more than you think.

Between water, fertilizer, lawn care services, seed, gardening equipment and other costs, Americans spend an estimated $40 billion caring for their lawns every year, according to "American Green: The Obsessive Quest for the Perfect Lawn." Not only that, but they also spend an average of 73 hours a year cutting grass, pruning and doing all the other tasks that help keep yards beautiful, according to the Bureau of Labor Statistics.

That's a huge investment of time and money that should be put to the best use possible. Here are some tips to help you frugalize your yard and save money over the long term.