There's nothing like homegrown vegetables, and there's no vegetable easier to grow than one that regenerates itself. With the help of a guide from DIY web site Instructables, you can now grow a bevy of onions from just one old onion bottom.
Onions are great. They not only provide flavour to many a dish, but they can also clean your grill — so there's no reason not to have a full bed growing in your kitchen at all times. All you need for this trick is an onion, a knife and a cutting board — things you probably already have if you're cooking with onions (if not, I'm very curious as to how you are cooking with onions). You'll also need some dirt — of which this planet has a pretty plentiful supply — and, if you choose to do so inside, some pots, although you can plant your onions directly in the ground if you prefer.
The process is extremely easy, and really just involves putting an old onion bottom in the ground and letting it regenerate it's roots — after which you remove the old onion and let those roots grow. You can also separate the roots to create new plants and they will regenerate themselves — theoretically giving you an infinite supply of onions. If you're going to overflow your kitchen with onions, though, be sure you know how to slice them like a pro and keep those tears at bay — we want to make sure the blood, sweat and tears going into your food is purely figurative.
Grow Onions from Discarded Onion Bottoms [Instructables]