Making a bog garden out of an old fountain
My new house has an old fountain in the yard. Concrete, flush with the surrounding ground, round, about six feet in diameter, with a stone "bird bath" in the centre with the "jet" in the middle of it. Straight edges. The "basin" is 20 inches deep.
I would like to convert this to a bog garden by adding a couple of inches of pea gravel, then filling the rest with triple mix (1/3 each of soil, peat and compost). I could also add sand to the mix if advisable.
The location is best described as having some sun in the morning, and dappled shade the rest of the day.
I am planning on doing this in the Spring. Plants on my list so far include some tropical punch from alocasia and colosia, maybe a canna, plus native cardinal flowers and a few sedges (Ice Dance and Bowles Gold). Maybe some horsetail, Jack-in-the-Pulpit and a Ligularia (Desdemona).
Any thoughts, suggestions, advice?