I started indoor urban-gardening about three years ago, completely on a whim (I'm a middle-ager now, and this seemed like an appropriate middle-aged hobby); but not knowing a single thing about gardening before then, most of the books I researched on the subject were just general gardening guides (or at the most, guides for "container gardening," whether that was indoor or outdoor in nature), and so my actual experiences have been rather hit and miss, with some crops that have grown in great and some that wither and die a few weeks after the seedlings started appearing in the first place.
So I'm glad to have recently come across an eBook copy at my local library of Millard's guide specifically to indoor gardening, because it's made me realize that I've been making a series of mistakes over the last few years -- for indoor gardening requires a different kind of soil makeup than outdoor, even if both are being done in containers, not to mention requiring a really specific kind of density to that soil, a specific amount of aeration, and different watering/misting schedules based on what you're growing. And in the meanwhile, Millard turns me on here to several other types of indoor gardening that I had never thought of before; like "microgreens," for example, which is when you cultivate things like salad plants right after they've grown just their first set of beginner leaves, then use them in places where you might also use things like bean sprouts.
Full of highly specific advice just for people growing their plants indoors, and full of great opinions about what works and what doesn't (like how hot peppers are ideal for growing indoors, for example, but green peppers aren't, or how cherry tomatoes do well indoors but full-sized ones don't), this is highly recommended for urbanites like me who need such advice, and are tired of sifting through general gardening guides to find the specific information they need.