Extracting oil can be challenging, but it sounds neat. Let me know how it works for you, if you try it. You can grow lots of stuff in containers. One project we did with my after school youth was a spaghetti sauce garden in a 5-gallon bucket. It had soil, tomato plant, bell pepper, basil and oregano plants. Seeds planted were: onion (3 bulbs), and zucchini. The kids took the buckets home for the summer. Some had more success than their parents had! We invited some of the kids back to the office over the summer for a food prep/nutrition lesson. We made spaghetti sauce from the stuff we planted in the buckets. The first week of school, we did the food prep again for those who didn't do it earlier. By "we" I mean that the kids did most of the chopping and cooking. Slap choppers came in really handy for this!

This year, I am going to try potatoes in Rubbermaid totes. Directions say you can just toss a little straw on top of the roots instead of hillng the plants. If needed, you can tip the tote on its side and keep covering with straw. To harvest you dump the bucket. Can't wait to try it!