I like
hugelkultur for the flexibility of the design. One little change, and it's gone from being arid-climate oriented to being sodden-climate oriented.
The
wood, so long as there's enough of it,
should act as a sponge, pulling the water from the soil where there exists more in the soil than the water, and releasing it slowly to the surrounding soil thereafter. That allows it, in most cases, to keep air spaces open so root zones don't asphyxiate.
If you're concerned, I would connect my hugelbeets to a system of excavated swales filled with woody matter, woodchips if you can get them delivered for free or cheaply (some urban arborists, for instance, will drop whole loads for free just to save them shipping and disposal costs). If you connect your hugelbeet wood sponge with the wood sponge of the swale, it will enable you to not only store more water, but distribute the excesses easier and more effectively.
Though this dynamic depends a lot on your soil. If you have drainage issues, the woodchips will improve them over time, especially if you add more, but if you have something like a calcium deficiency making your clay gloopy when sodden and cementitious when dessicated, you might need to add something like gypsum to your soil, especially at the bottom of your hugelbeets, such that the clay particles have something else to adhere to other than themselves, opening up the soil structure to allow water and air.
-CK
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein