One bale (33 lbs.) will cover your 4' x 6' coop about
3 inches deep. But a true comparison requires more than just the cost v coverage. I've done a LOT of research on hemp bedding for poultry, specifically for use with the deep litter method in the coop. I'm sharing what I learned here in case it is helpful. I recognize everyone develops a fondness
for their favorite materials. So use what works best in your area and situation.
Technically, the deep litter method calls for starting with at least 4" so you'd use about 1 1/3 bales to start. (This is to ensure the poop moisture never reaches the bottom of the coop since that would smell and put off ammonia.) As the poop accumulates in specific areas such as under the roost, you can remove the excess poop, fork/rake it into the litter, or rake if off to the sides/corners (unless your coop has metal sides in which case the wet poop will rust it). Even with 10 chickens, this should last you quite a while. However, the general consensus I found in my research is that it is best to add some fresh litter periodically, sprinkling it lightly in the same places where the poop tends to accumulate. Even if you see a lot of poop, the litter is still good if it is dry and there is no smell. Coops using deep litter with hemp can go without cleaning for a far longer time than with other common litter materials. This is simply because it is more absorbent. What's nice is that this product is now very low dust too. ( I don't think that was the case when it was first introduced.) So, spreading additional bedding and cleaning the coop doesn't require a hazmat suit like straw or wood shavings. (I am drawn to that characteristic like a magnet!)
There is also a lot of research and observation that points to a lessening of coccidiosis outbreaks when using the deep litter method. (There are at least 11 strains of this nasty coccidia, a protozoan parasite. So your chickens can get "it" again and again. But there are microorganisms that think coccidia are yummy and they make a home in the litter. That's why some recommend you do not clean out a deep litter system completely. Rather they recommend you remove no more than half its volume at a time and replenish by mixing new material with the old.
Last, I don't have a distributor in my state that supplies hemp bales. Since I had a couple of coops and a brooder to switch over, I ordered in volume to get the shipping costs down. Perhaps you can pool your order with your BYC neighbors to do the same. Sources for
hemp by the bale include Hemp Solutions and American Hemp. (Due to BYC rules on posts, I cannot provide a link. But if you Google each of those names, their sites will be the first in the listing, excepting any potential Google ads). The bales cost pretty much the same. It's cheapest if you can pick it up yourself. If not, the distance between you and the distributor can vary the shipping costs. So shop the
shipping prices before ordering!!!