Mr. Burbank's Ideal Soil
Such piles of soil as that here shown are always at hand in and about Mr. Burbank's greenhouse. The soil consists of about fifty percent of clean, rather coarse, sharp sand; forty percent of good pasture or forest soil, containing leaf mold; and about ten percent of finely ground moss. This makes an ideal soil for the seed boxes, and seeds of any and every kind may be germinated In it.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 7 Chapter 1