Hugel Idea/Questions

Hey guys, I wanna put in a Hugul bed soon, as in before it gets too cold in Tampa(:3), I made a diagram after reading a bit to get a plan for the materials, lemme know what you think of my "design."
The third picture has some questions, I know you guys don't know much about my space, just lemme' know what you think is a good size for a Hugul bed, and what you think of the keyhole design (I read about it in Hemenway's book and I want to try it out.)
Any feedback is greatly appreciated, thanks.
Hugul Album
Permie Prezi Click the forward button twice to get to the information house, 11 and 12 on the path are the hugul pictures, the map doesn't have dimensions yet, I realize it's a big oversight and am working to correct it, it's a work in progress prezi xD.

Are you going to place it right there by your back door? If so, you might want to place the entrance of the keyhole facing you for better ease of access. Generally I run my Hugelkultur beds on contour to catch water as it flows across my property. Looks pretty flat where you are, can't really tell from the picture. Anyway, in my scenario, I like to run them in lines, but I don't see any reason way a keyhole shape would not work. I think the keyhole design is just to allow for ease of access when tending to the garden bed. Probably isn't necessary for what you are doing, but if you want it to look like that, go for it! You would just want to figure out where the sun is hitting and think about what you are trying to grow. As far as length it really doesn't matter, and they say an optimal height is pretty high, like a lot higher than I want to do in my suburban backyard, but I have had wonderful success with 3 feet high Hugel beds, using wood covered with soil and then a lot of hay mulch with some compost on top. Good luck! --Jonathan

Your link took me to an add page that I was unable to escape from on a mobile phone. I had to close the window and come back.

Edit - I'm on a laptop now and all is well with the website.

I assume you're dealing with sand. In order to hold lots of moisture, it would be good to sink wood deeply into the ground. Larger beds have less edge exposed to sun and wind, so it's easier to manage water. Cover the bed and surrounding soil with a generous quantity of leaf mulch. You can't have too much leaf mulch. If you can obtain some clay, that would help in soil creation and moisture retention.

I would turn the keyhole around so from the porch you can walk down and into the mound keyhole, if you really want a keyhole style. Like Dale, I think you will be best served if you dig down to place your first logs, the sandy soil of Florida begs for this method and it will allow you to build on a more stable base, give you more moisture retention over the long run.

In your area, I would think of working the wood from largest (bottom as in your drawings) to smallest, instead of two layers of wood, per your drawings, I would shoot for at least three and probably four layers of wood for the mound build. I would also use straw/moss mixed together for my first layer of cover layers. You have the right ideas, just need to think more on how to best create water retention in the mound, your sandy soil drains very well and so you need to set your layers to put the brakes on the water as it will want to drain away. Good things to use for that are peat moss/sphagnum moss, instead of making it a layer, mix it with some of your other layer materials (wet it first then as you build wet each layer as you go, this will charge the mound with as much water as possible). Wetting down each layer will also give you an indication of how well your mound will hold water once completed. I would also add coffee grounds (if you have them or can get them) for a little more nitrogen boost for the beginning.