This section is from "The Horticulturist, And Journal Of Rural Art And Rural Taste", by P. Barry, A. J. Downing, J. Jay Smith, Peter B. Mead, F. W. Woodward, Henry T. Williams. Also available from Amazon: Horticulturist and Journal of Rural Art and Rural Taste.
Dr. Nichols, of the Boston Journal of Chemistry, made an analysis of the ash of home cuttings of a Black Hamburg Grape vine, with the following results: Potash, 29 parts in 100; phosphate of lime, 19 parts in 100; carbonate of lime, 13 parts in 100; soda, 3 parts in 100 ; magnesia, 4 parts in 100 ; with small quantities of iron, manganese, silex, etc. The fruit evaporated to dryness, and ignited to obtain the ash, gave of - potash, 34 parts in 100 ; phosphate of lime, 11 parts in 100; carbonate of lime, 9 parts in 100, with small amounts of earthy substances. From these results he finds mineral food, which the vine and its fruit require in the largest quantity, is, first, potash; second, phosphoric acid; and, third, lime. For a border of thirty vines, at least a barrel of-bone dust and six to eight of ashes should be used; about three pounds of Epsom salts (sulphate of magnesia) and five of sal-soda (carbonate of soda) will be required for each barrel. A layer of soil should be placed between each two layers of the bone, ashes and lime.
The layers of ashes should be thicker than of the bone dust.