Composted manure is $1/40-pound sack at HD, Wal-Mart,Lowes. That gets you a fine wood mulch mixed into the manure.

Since you bamboo is doing OK now, I'd keep it simple and cheap with just the composted manure, as thick as you can afford it.

Cher-
Your plans sound good, except for the food scraps, which I agree are just going to attract raccoons (and rats and squirrels). I suggest you just throw the scraps in your composter, and use them that way. The situation you describe sounds a little like mine at my last house. I was in a pretty heavily wooded lot with 100' tall firs that I was not inclined to take out, so it was pretty shady. We finally decided to have an arborist limb the trees up to about 30'. The trees looked better and the light increase was substantial. That year my grove of Yellow groove bamboo -- which had been around for 30 years -- acted like it was on steroids. Just that increase in the amount of light made the the new culms shoot up 5'-10' higher than ever before. Other species, which had been doing ok previously, also started to put up significant numbers of new shoots and get leafier. If you have the means to increase the light to your bamboo, that may help the growth as much as anything.

Skip the gypsum unless your soil is alkaline. Replant in existing soil (no amending of backfill), mulch afterward. In nature most organic litter occurs on top of the ground, not in it. That is what most plants are used to. Many vegetable plants and annual plants are developed from wild species that occur on disturbed sites, plus these have small root systems so it is more natural and feasible to amend planting beds for them than with permanent plantings of large plants like bamboos.

no matter what you add:
compost
other organics
sand
fertilizer.....

it won't grow to potential without enough water. Try to keep it moist and you'll get better results.

Ron-
I've got a question for you about your post. I've heard that mixing some gypsum in with really clay-like soil is beneficial. In fact someone told me that they kept having lots of failures in gardening until they amended their clay soil that way. They dug down about a foot below the planting zone and mixed the gypsum into some of the clay, partially refilled the hole, and then backfilled the planting layer with unamended soil. Your thoughts, please?

Gypsum works on clays that are high in Sodium. On other soils the act of working it in gives the benefit seen.

Here is a non technical website whitneyfarms and a more technical paper Iowa State University paper

Bill

I have used a product called "Structure" worked into my clay soil. It is made of ceramic granules that allow drainage but still retain moisture. I also use compost worked into the soil with grass clippings and compost as mulch. It seems to work so far.

Pile on the mulch, use spoled hay, shredded leaves, wood chips, grass clippings a inch or two of rotted manure, any compost you can find. As for kitchen wastes so what if the racoons get a good feed you can rake the stuff back over the scraps when they are done,

each year i normally go and get several loads of leaf mulch that the city gives away for free in spring, to amend the ground. of course if they dont give it away, you can allways buy it for about $8 a tractor scoop and use that. works wonders in the garden.