From the laundry basket of the Homegrown Mama
Some root vegetables make it obvious when they are ready to be harvested. Onions, parsnips and shallots are generally ready to be harvested once the leaves die down. The onions and shallots should stay in the ground for an additional 2 weeks after the leaves fall over. After that, you can dig them up, shake the dirt off and store them for the winter. Parsnips can be dug up and eaten as soon as you notice the leaves falling over. If you aren't ready to harvest yet, you can toss a layer of hay over their tops to protect them from frost, but in my opinion, it'd be better to just dig them up.
Carrots, turnips and beets can be harvested when they are still fairly immature, such as when you thinned them earlier this year. I hope you were able to enjoy them while they were so tender. As they grow, you want to look for the tops to sprout on the carrots and the beets to be close to the size of a golf ball before harvesting.
So here you are and you've already harvested all your root vegetables or you are preparing to and now they are just piled up on the table... what should you do with them? Well, this is my moment for shameless self promotion. Dice up those parsnips, carrots, onions and add in some apples and spinach and you've got yourself a lovely side dish. Add in some chicken or white beans and it's a full meal. Healthy. Hearty. Filled with those hardy root vegetables that hid underground while you harvested the rest of your garden.