Tilling depth.

Hi,
I've bought myself a smallish rotovator/tiller/ cultivator and I've read some where that the soil shouldn't be tilled any deeper than four inches. Is there any validity to this or should I let it go down the eight or more inches that it could go down. I intend to use it once at the start of the year and once at the end, that's all.
Paul

 

As long as you dont go below the topsoil level,
When hand digging I usually go down one fork depth, (spit), which is about all the top soil I have below that is clay and stones.

 

I have heard this before about the four inches thing. Apparently, its the "modern" way to do things.

In my own opinion, the tilling deppth really depepnds on two things. First, the kind of machine being used. Some of the smaller electric or two stroke tillers wont go down to four inches anyway. Even on the sandy loam that I have, they are not really usefull for more than hoeing.

Secondly, a lot depends on the type of gound. Traditionally, clay or heavier soil is "double dug." That means going down one spade depth, the loosening up the next spade depth with a garden fork. Thats a lot more than four inches. Also, organic material will be added.

I suppose that before an accurate answer to the question is given, we would need to know the type of soil, as well as the type of tiller being used.

 

Double digging, not something I've ever tried, just too hard and claggy down there, the back wouldn't stand it these days either.
I have one of those small tillers you mention @Sandy Ground but to be honest they are hard work in themselves and I have a theory they kill off all the worms.

 

@pete if some of these people that design garden machinery actually got out from behind their computers and spent a few days in a garden using them, weäd soon have machines that are easy to use. Who knows, doing that might even save the lives of a few worms in the process!