Easy Recordkeeping
Gardenwriter and blogger Amy Stewart once ranted about seeing plant tags stuck in the soil in front of the plants they identify and 
I had to agree with her - they sure spoil the natural look. So I chimed in on this pressing issue, stating emphatically that HERE'S what people should do with their plant labels. They belong, as Amy correctly noted, NOT in the garden but in the GARDEN BOOK, which I assume readers have because they're serious about their gardens, right? But in the unlikely event that I'm wrong about readers all having garden books, I'll wax rhapsodic for a while about my own and hope it'll convince the slackers to get with it, organizationally.
Picture me, if you will, showing people around my garden. They ask about a plant and I can tell them exactly what it is and they can go buy one of their own. Visitors love it when gardeners can do that! Or if I want one more of something, I can buy one more of the same plant because I know what it is. See how this works? When someone asks how fast a plant grows I can tell them oh, I bought it in 2002, so there you see three years of growth. Again, nifty information to have at your fingertips. Same goes for the nursery that sold me the plant and how much it cost. See, it's all there in THE BOOK.
How it Works
Couldn't be simpler. I make a page for each plant that's currently in the garden and tape the label to it, then write down the date of acquisition and the source. If there's no label I write what I know about the plant, from whatever source. I have a tab for annuals, perennials, shrubs and trees. If I'm super busy, I just tuck the label in the book until I have more time - like winter. At the very minimum, keep the tags somewhere where you can find them, like a big envelope.
Now at the risk of seeming a tad compulsive, maybe a Myers-Briggs type J (guilty as charged), I'll mention in passing that I also have binders for bulbs, for plans, and for miscellaneous gardening information. But please, readers, don't hate me because I'm organized.