Various plants (in no particular order) that you can regrow from the food you already have! Woot! Way to reuse and recycle! I constantly have green onions and celery growing. (And potatoes/sweet potatoes but that just because they decided to do that in my pantry) Do you guys regrow any of your food?
Apples- http://www.ehow.com/how_2135774_grow-apple-seeds.html
Tomatoes- http://www.ehow.com/how_5581958_grow-tomatoes-fresh-tomato-seeds.html
Potatoes/Sweet Potatoes- http://www.gardenguides.com/117543-plant-cuttings-potatoes.html
Green Onions- http://www.17apart.com/2012/02/how-to-grow-green-onions-indefinitely.html
http://tipnut.com/nifty-food-plants/
Leeks- same technique as green onions
Carrot Tops- http://www.gardeningknowhow.com/children-in-the-garden/grow-carrot-tops.htm
Pineapple- http://www.rickswoodshopcreations.com/Pineapple/pineapple.htm
Romaine Lettuce- Same technique as celery
Cabbage- Same technique as celery
Celery- http://www.17apart.com/2012/02/growing-celery-indoors-never-buy-celery.html
Avocado -http://www.thehungrymouse.com/2009/09/09/how-to-grow-an-avocado-tree-from-an-avocado-pit/
Lentils- http://foodstoragemadeeasy.net/2009/02/19/how-to-grow-sprouts/
Pumpkin- http://pinterest.com/pin/98375573080950437/
Ginger- http://www.gardenswag.com/2011/12/5-foods-you-can-grow-from-kitchen-scraps/
Garlic- http://www.gardenswag.com/2011/12/5-foods-you-can-grow-from-kitchen-scraps/
Bonus: Bok Choy - http://www.17apart.com/2012/02/how-to-regrowing-bok-choy.html
