James - no I haven't used any membrane because I want the gravel to be slowly incorporated into the soil and improve the surface drainage. It gradually disappears and so after a few years I heavily topdress with more. I know that some growers with sand beds put in a barrier to keep the sand free of soil, though I haven't done this elsewhere in the garden. It may have been wise to do it because worms and ants are steadily bringing up a lot of soil. I will probably do this next time.
Trond - I always used to think myself fortunate until parts of the garden began to revert to wilderness! Much of the garden is fairly intensively planted (ie: I like plants too much!), and some does need to go back to more naturalistic and wild woodland planting, which tends to happen by default.
Dr. Timothy John Ingram
Faversham, Kent, UK
I garden in a relatively hot and dry region (for the UK!), with an annual rainfall of around 25", winter lows of -10°C and summer highs of 30°C.
Further discussion of weed fabric and sand beds is continued here:http://nargs.org/smf/index.php?topic=965.0
Rick Rodich zone 4a. Annual precipitation ~24 inches
near Minneapolis, Minnesota, USA