This is why it's so good to talk to locals!
Jen Swanson wrote:Ok, so learn something new every day. I talked to some friends who have a huge hugel bed and they built it by digging a big hole in the ground and putiing in tree trunks first. The soil around here does have a good portion of clay in it but does drain well. The center of the bed is probably 3 feet about soil level and the whole thing is very fertile. They use it as a vegetable bed.
Jen Swanson wrote:Hi Mark -
Please don't dig a big hole in the clay and put your hugel bed in it. Clay does not inherently drain well. When you dig a hole in clay, put plants in it and fill it with material other than the clay, it creates a bowl that holds in water and it doesn't drain well at all. Most plant roots detest being soggy so this situation is very unhealthy. And nothing ever remedies this situation other than replanting the plant correctly. In fact, research shows that anytime you dig a hole in the ground to plant and you fill the hole with something other than native soil, the hole will not drain well. Water does like to move from one type of medium to another.
Roots are the same way. They will double back into the soil they were planted in instead of growing into the clay, creating a rootbound plant. This is the same reason why you should not put gravel on the bottom of a pot.
Instead, put your hugel bed on top of the clay. Save your back. And, over time, it will break down and the released nutrients will add organic matter to the clay, loosen it up and make the microbes in the soil happy, thus improving the soil. You have a good start going with the leaves and wood chips you put down last fall.
I agree totally about not using pressure treated. There are some threads such as this one ( https://permies.com/t/163796/Ideas-Trellis-Gardening ) with pictures of raised bed alternatives. If you have a local free-cycle type of program/website you may be able to gather materials slowly. I've got almost enough breeze blocks to build a second breeze-block bed two blocks high which have come from a gentleman who knew I wanted more and was able to trade cheaply for them. My new 30" high beds I mentioned were built out of HT (heat treated) packing skids. I find them time consuming to build, but the only expense was the brackets for the corners and the gas to collect the skids from a hardware store less than 5 km away. We happen to own a utility trailer though, so if you don't have access to something like that or a pick-up truck, or a really good cargo bike, that's a problem. The nice thing about the way I made my skid beds is that they look very nice, which in an urban area is a plus. Not that you can actually see much of them at the moment - with the heat this summer, the beds have tomatoes and tomatillo plants hanging off the sides to the point I can hardly get past!
I would like to do all raises beds but don’t really want to use pressure treated 6x6 any more and don’t have materials otherwise.
What is the slope of your land and where and how does water currently drain? What have people done in your area that have *really* wonderful gardens?
My plan for the surrounding clay where I will establish new beds is to “break” the soil once or twice a year with a broad fork. This will aerate to about 14” deep. My thinking was that this would improve the surrounding clay soil over time. Now I’m thinking this may not be sufficient given what you laid out for me.
Douglas Alpenstock wrote:Improving straight clay is a big, long term job. I dunno, there are a lot of moving parts here, but I think this could be a good approach. In the right place, I would consider doing the same thing.
What is the general climate? Local drainage profile? If it gets super wet, can you dig drains/pits to shunt away the excess water and prevent ponding?
P.S, welcome aboard Mark!