:rolleyes: ;) 8)
From the High Desert Steppe
of the Great Basin and the Eastern
Escarpment of the Sierra Nevada Range
Located in Reno/Sparks,NV zone 6-7http://www.flickr.com/photos/sierrarainshadow/
John P Weiser
Back in 2005 i built this experimental riversand/gravel bed edged with small troughs and railway sleepers.The area is approximate 6 square metres with the mix mostly only 100mm deep ,with weedmat underneath, rising a little on the ridges in the middle.
Most of the plants in the plot don't require sand bed treatment,(in as much as they can be found growing well in other soil based rock gardens),--my expirement was to see what could survive in a different environment and of course to try and successfully cultivate some of the more difficult genera.
Following pics show the bed after tidying and recoating it with various sized rocks pieces last weekend.
Bottom of the South Island New Zealand
Zone 8 maritime climate
1100mm,(40 in),rainfall p.a.
Nil snow cover
Just last fall, I also built a raised box with the bottom lined with sheet plastic for the same purpose - exclusion of tree roots. Also experimental. Unfortunately, the sloping of the terrain is only slight, so I drilled extra holes at the bottoms of the sides (and yet another looming problematic possibility). It is not an alpine bed, but I will be monitoring the affects closely. The perched water table effect kinda scares me since it is more of a woodland soil mix and not as free draining.
Rick Rodich zone 4a. Annual precipitation ~24 inches
near Minneapolis, Minnesota, USA
Dave, aside from increasing your experimental rock-gardening space, it makes a very fitting background for your troughs.
Calgary, Alberta, Canada - Zone 3
-30 C to +30 C (rarely!); elevation ~1130m; annual precipitation ~40 cm