Uses for radish and turnip greens?
Turnip greens are a very common food in Southern US cooking. The smaller baby leaves are good for salads since they have a milder flavor and are more tender. Larger leaves are best cooked. 

You'll definitely want to rinse them thoroughly in a sink full of cold water. They tend to have a lot of dirt and bugs on them. Just fill the sink and dump your greens in, jostling them around with your hand. This allows the sediment to sink to the bottom.

The typical southern preparation involves boiling them for 30 minutes, dumping the green water (and much of the bitterness), and then boiling another 15 minutes with some bacon or ham hocks. They are then drained, salted to taste, and served with either tabasco, vinegar (malt is good), or butter.