This section is from the book "The Gardener V3", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
"When the Peach-house occupies a site where the soil and subsoil are uncongenial, such as poor sand, an irony gravel, or a cold stiff clay, the whole should be removed to the depth of 3 feet, and the site surfaced with a 3-inch layer of concrete, giving it an even slope from the back wall to the front of the outside border in the case of lean-to houses; the slope to be from the middle of span-roofed houses to the front on each side. Over the concrete run tile-drains at right angles across the border, 8 feet apart, into a main drain in front, and below the level of the cross drains. Over these drains and the whole concrete lay 8 or 9 inches of broken bricks, or coarse gravel with the sand sifted out of it, and blind the whole with finer gravel; over this lay a thin turf, grassy side downwards, and the site is ready for the soil. This leaves about 2 1/2 feet up to 3 inches above the front lintels or arches of the house for soil; and allowing for the necessary slope of the border, at the extremity or front it will be a little less than 2 feet. I am not an advocate for very shallow borders, when the drainage is as efficient as has been described. This matter should, however, be decided to a certain extent by the nature of the soil and the amount of rain that falls in the locality.
When the soil is heavy and the locality very wet, the borders will be deep enough at 2 feet. Their width should be regulated by the width of the house. A lean-to house 16 feet wide will require an outside border 16 feet wide, thus giving 16 feet for each of the two sets of trees, the one set on the back wall and the other on the front trellis. Where the subsoil consists of a clean open gravel, concreting is not necessary, and the natural drainage being good, less artificial drainage will suffice.
It is an established fact that all stone-fruits can be grown to the greatest perfection in strong-holding soils. This fully applies to the Peach, for it is on a strong calcareous loam, resting on a dry bottom, that it thrives best. The healthiest Peach-trees on open walls we have ever seen were grown in a deep strong loam, resting on an immense depth of chalk; and, generally speaking, the limestone districts of England produce the finest outdoor Peaches and other stone-fruits. These facts apply with equal force to the culture of the Peach under glass. To produce the most healthy, fruitful, and long-lived trees, the best soil with which to form a Peach-border consists of the top spit of some old pasture-land of a calcareous nature. It should be taken to the depth of 6 inches, inclusive of the short verdure peculiar to such land.
When carted in, stack it into something like large potato - pits; and if it can be allowed to lie for eight or nine months before being used, all the better. "When it cannot be so arranged, it can be used as it comes from the field. Before it is wheeled into the border it should be roughly chopped up with a spade. Then add to every twelve cartloads one of old lime-rubbish, one of charred wood, and 2 cwt. of half-inch boiled bones. Where neither lime-rubbish nor charcoal are procurable, an equal proportion of charred soil can be substituted. These should all be well mixed together and wheeled into the border when in a dry state, making it rather firm by beating it with the back of a fork, and allowing 2 or 3 inches for subsiding. As in the case of Yine-borders, I recommend that only part of the border be made at first, the rest to be added in 3 or 4 feet widths, as the roots of the trees extend. In thus making a Peach-border with fresh, turfy, strong loam, I do not advise the use of any manure except the few bones, which stimulate slightly over a long series of years. Common manure, either from the stable or cow-house, is undesirable at first, on account of the natural tendency of young Peach-trees to make rank, unfruitful growths.
The borders can be enriched in after-years, when the trees require it, by top-dressing and watering with manure-water.
I would be sorry to convey, by these directions, the idea that very considerable success in Peach-culture is not attainable except when fine fibry calcareous loam can be had from an old pasture. No doubt the character of the soil in some gardens demands that all, or nearly all, the soil for the Peach-border should be exchanged for some of a very different character. Where the natural soil is very sandy or gravelly, and shallow, satisfactory results need not be expected unless fresh soil to some considerable extent be added to it, or wholly substituted for it. In this case, and when strong loam cannot be had, some strong soil, of a sound clayey nature, should be mixed with the light soil; and the parings of roadsides, with the herbage and roots, will also assist in making the soil more suitable. Where, on the other hand, the natural soil is a very strong, adhesive clay, its unsuitableness in that respect can be greatly remedied by burning a third of it and mixing it with the original, and by also adding to it a portion of road-scrapings. Where the natural soil of a garden, however old, is of a loamy nature, tolerably deep, and resting on a dry healthy subsoil, and where the fine loam I have described cannot be had without great expense, I do not hesitate to say that very fair success in Peach-culture is attainable by merely trenching it, and mixing in a few bones and a little lime-rubbish. These remarks are intended to encourage those who cannot get the turfy soil that may be considered first-rate, but without which comparatively good crops of Peaches can be produced.