Raised Bed Soil Help please?

[lapk78]

Hi All, I posted a similar request under "General Discussion" but got no replies. (Do raised beds count as "containers"?) In the past I have used Earthtainers, but after a couple years off, I now am trying my hand at raised bed gardening. The two new beds are 4'x4'x15". I don't quite know what type of mixture to fill the beds with.

I have recently learned of Hugelkultur, and am thinking about adding some small branches/logs at the bottom, mainly for the moisture retention aspect. Incidentally, I'm in San Antonio, TX (zone 9a). But beyond that, I'd like to buy/make a good soil. Should I make a similar mix to that of the Earthtainers I've used in the past? Or is there something better that you'd like to recommend?

Thanks in advance for any input!