In my experience, you've made a bit too shallow hole and put not enough smaller diameter branches in the top layers. Also, the soil layers seems a bit thin and the whole structure is a bit narrow and tall, while it behaves better in time if it's wider and stockier.
Be prepared for nitrogen deficiency when planting in it, so my advice is to put a shovelful of compost or vermicompost in the hole for each plant.
Geoff did not actually made hugels as per Sepp's specification. Sepp works in a very different way and scale. What the team did in Jordan was pile biomass, but it was mostly farm residue, tree leaves, palm fronds, annual plants, not hardwood logs. The temperature differential results in condensation and hence some minimal moisture being added to the soil, at times where none is otherwise available. It must be also noted, that they had drip irrigation for all the plants they put in the initial round of planting, so the deep mulch is mostly for keeping the water in the soil. Decomposition happens very slowly in dry sites, if the biomass is inadequately moist.
RE: Permaculture gardening: Building a hugelkultur.