Organic Gardener's Composting by Steve Solomon

_Kelp meals_ from several countries are available in feed and grain stores and better garden centers, usually in 25 kg (55-pound) sacks ranging in cost from $20 to $50. Considering this spendy price, I consider using kelp meal more justifiable in complete organic fertilizer mixes as a source of trace minerals than as a composting supplement.

There is a great deal of garden lore about kelp meal's growth-stimulating and stress-fortifying properties. Some garden-store brands tout these qualities and charge a very high price. The best prices are found at feed dealers where kelp meal is considered a bulk commodity useful as an animal food supplement.

I've purchased kelp meal from Norway, Korea, and Canada. There are probably other types from other places. I don't think there is a significant difference in the mineral content of one source compared to another. I do not deny that there may be differences in how well the packers processing method preserved kelp's multitude of beneficial complex organic chemicals that improve the growth and overall health of plants by functioning as growth stimulants, phytamins, and who knows what else.

Still, I prefer to buy by price, not by mystique, because, after gardening for over twenty years, garden writing for fifteen and being in the mail order garden seed business for seven I have been on the receiving end of countless amazing claims by touters of agricultural snake oils; after testing out dozens of such concoctions I tend to disbelieve mystic contentions of unique superiority. See also: _Seaweed_.

_Leather dust_ is a waste product of tanneries, similar to hoof and horn meal or tankage. It may or may not be contaminated with high levels of chromium, a substance used to tan suede. If only vegetable-tanned leather is produced at the tannery in question, leather dust should be a fine soil amendment. Some organic certification bureaucrats prohibit its use, perhaps rightly so in this case.