if you're dealing with a small space your best bet may be to just buy a little pot that suits your particular needs. cheap nursery pots are around a buck or so in the smaller sizes. i've seen some real badass diy pots, too. one guy took a laundry basket and lined it with that black weed block stuff. if you need the pot to be "short", look into tupperware or bus buckets. keep in mind though that cannabis roots grow down more than they grow out, so a short pot might not be ideal.