We love our gardens. Much like we do with pets, many of us spend more money on gardening stuff than we do on essentials for ourselves (well, gardening stuff is essential, isn't it?). This year, whether you have someone to garden with or not, celebrate Valentine's Day in the garden. It falls on a Sunday, so there's no excuse. You don't have to buy a thing to celebrate Valentine's Day. Here are some of our favorite ideas for celebrating love…