I'd like to have my first garden this year but don't have enough sunlight in places I could cultivate. Instead my best sunlight (about 3/4 of the day) hits the end of my driveway, which is graveled. My first instinct is to buy several whiskey barrels but they are usually costly (maybe $25 apiece?) and I'm looking for enough plantings to use 3 or 4 of them. I can get similar sized 55 gal. plastic barrels for free from my local car wash. I would cut them in half and use like a whiskey barrel. I used one for a portable bait fish tank after several thorough washings to remove the soap residue. I'm worried I may not be able to reliably get it clean enough for growing vegetables though. I'll need to go look at one again and see what warnings are on the label. I would get more growing space with a rectangular box than 4 round barrels. Short of buying 1x10 or similar sized untreated lumber (starting to sound expensive) what else might I use? I was thinking of maybe a 4'x'5' box 18" deep but that starts to hit $100 to buy the necessary board feet from Lowes. What are some less expensive options? 5 gallon buckets?