Answer: In my experience you usually do need to order these in large quantities. You might be able to ask a local landscape installation crew to save you some pots in the sizes you need, or ask a local nursery that does their own potting to sell you a few if you need brand new ones. Alternatively, you might be able to use inexpensive plastic buckets from the discount store instead of "official" pots. I'm sorry I don't know of a retail source.
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