At Indore, Howard built a covered, open-sided, compost-making factory that sheltered shallow pits, each 30 feet long by 14 feet wide by 2 feet deep with sloping sides. The pits were sufficiently spaced to allow loaded carts to have access to all sides of any of them and a system of pipes brought water near every one. The materials to be composted were all stored adjacent to the factory. Howard's work oxen were conveniently housed in the next building.
Howard had been raised on an English farm and from childhood he had learned the ways of work animals and how to make them comfortable. So, for the ease of their feet, the cattle shed and its attached, roofed loafing pen had earth floors. All soil removed from the silage pits, dusty sweepings from the threshing floors, and silt from the irrigation ditches were stored near the cattle shed and used to absorb urine from the work cattle. This soil was spread about six inches deep in the cattle stalls and loafing pen. About three times a year it was scraped up and replaced with fresh soil, the urine-saturated earth then was dried and stored in a special covered enclosure to be used for making compost.
The presence of this soil in the heap was essential. First, the black soil of Indore was well-supplied with calcium, magnesium, and other plant nutrients. These basic elements prevented the heaps from becoming overly acid. Additionally, the clay in the soil was uniquely incorporated into the heap so that it coated everything. Clay has a strong ability to absorb ammonia, preventing nitrogen loss. A clay coating also holds moisture. Without soil, "an even and vigorous mycelial growth is never quickly obtained." Howard said "the fungi are the storm troops of the composting process, and must be furnished with all the armament they need."
Crop wastes were protected from moisture, stored dry under cover near the compost factory. Green materials were first withered in the sun for a few days before storage. Refractory materials were spread on the farm's roads and crushed by foot traffic and cart wheels before stacking. All these forms of vegetation were thinly layered as they were received so that the dry storage stacks became thoroughly mixed. Care was taken to preserve the mixing by cutting vertical slices out of the stacks when vegetation was taken to the compost pits. Howard said the average C/N of this mixed vegetation was about 33:1. Every compost heap made year-round was built with this complex assortment of vegetation having the same properties and the same C/N.
Special preliminary treatment was given to hard, woody materials like sugarcane, millet stumps, wood shavings and waste paper. These were first dumped into an empty compost pit, mixed with a little soil, and kept moist until they softened. Or they might be soaked in water for a few days and then added to the bedding under the work cattle. Great care was taken when handling the cattle's bedding to insure that no flies would breed in it.
Though crop wastes and urine-earth could be stored dry for later use, manure, the key ingredient of Indore compost, had to be used fresh. Fresh cow dung contains bacteria from the cow's rumen that is essential to the rapid decomposition of cellulose and other dry vegetation. Without their abundant presence composting would not begin as rapidly nor proceed as surely.