At the greenhouse (Millennium Farms) where I purchase many of my heirloom veggies, the owner has a barrel filled with strawberries, a bigger version of the clay strawberry planter.
He used a 50-gallon barrel with the top cut out of it and several rows of holes drilled in it in which to plant the strawberry plants. Then he put a piece of PVC pipe down the middle of it after drilling holes in it to distribute the water throughout the height of the barrel. He put landscaping fabric against the sides to hold the plants in place with a hole cut for the plants' roots. As he filled it, he put gravel directly around the pipe to discourage dirt from plugging the holes.
It's a great idea, a good way to get a lot of yield from a small footprint, an entire strawberry patch in a 5-foot circumference circle. I cut the barrel for one today with two dozen 2-inch holes for plants (and the top). I will make one with fewer holes for herbs, planning parsley or basil on the top. I figure placing a cover over the basil as the weather cools will prolong its growing season.
For the strawberries, once they are established (when I actually get fruit!), it will be an easy matter to construct a "cover" to keep out birds so we get the berries.
I'll keep you posted as to how this works, confident that it will work very well. Any suggestions about what, other than strawberries and herbs, might do well in this type of planter?
Glenna