This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
The best site for a French garden is one not too far from a supply of good stable manure; where water can be obtained in abundance either from a company on reasonable terms, or by means of a well, stream, or pond; and where the ground is of fairly good natural texture with a gentle slope between the south-east and south-west. The site should be protected by low fences, hedges, or walls on the northern and eastern sides. It should also be sheltered from south-westerly gales, as these may do much damage in lifting the lights and cloches in tempestuous weather. A position some little distance away from the sea should be chosen in any case, otherwise the winds carrying salt spray are likely to do much injury to the tender foliage of the various crops. So far as shape is concerned a square or rectangular piece of ground is most suitable, as the beds are made in parallelograms running east and west, and the intersecting pathways are at right angles to them with the waterpipes beneath.
If wooden fences or walls surround the garden they may be utilized for the cultivation of Peaches and Nectarines on the south aspect, and Apples, Pears, or Plums on the east and west. The borders all round the fences are very useful for different succession crops, owing to the varying aspects, and the main pathways are useful to enable the produce to be brought from the frames or beds without too much circumambula-tion. If funds permit, it will pay to have a light railway put down on these, with a turntable at each main junction. Over such light railway, trolleys holding large quantities of produce can be trundled along readily from the frames, cloches, or beds to the packing shed, and will save a good deal of time and labour and consequently money.
It is impossible to run a garden on the lines laid down by French maraichers without a good supply of: (1) good stable manure; (2) frames and lights; (3) cloches or bell glasses; (4) water; (5) mats. And to these must be added the personal qualities of cultural skill and dexterity, intelligence, and business ability and application, and of course a fair amount of capital. These are all cogs in one big wheel, which if worked as a whole lead to success, but if worked as units and without due regard to their bearing or influence on each other are almost sure to lead to disaster.
This should be the best manure from stables, and a good supply should be readily obtainable. Cow manure, pig manure, etc, are valuable in small quantities mixed with stable manure, and so also are the leaves of Oaks, Beeches, Sweet Chestnuts, and Elms, as they generate and retain heat for a considerable period.
The quantity of manure required annually will depend largely upon the number of frames and cloches used, and the first year will be more expensive than those succeeding. Taking one three-light frame (13 ft. by 4 ft. 5 in) as a unit (and thirty cloches as corresponding in area), about 2 tons of stable manure per frame would be required for the season's work. Thus a garden containing 300 frames and 3000 cloches would require about 800 tons of manure annually, at a cost varying from 4s. to 7s. per ton. The first year or two, however, it would be well to have about 1000 tons, in case of accident, for extra linings, etc.
The manure should be brought in at intervals, from August to November, so that it may not be all fresh or all stale at one time. The manure should be stacked up in square heaps if dry, and should be watered and turned occasionally to bring it into a proper state for making up the beds.
Early in the season very little fresh hot manure is necessary, owing to the mild weather, but in the depth of winter plenty of hot steaming manure must be used. This is not only necessary to generate the requisite heat in the frames and cloches, but also to maintain it by "lining" the frames, that is, banking them up outside and between each other. In this way only can the heat be maintained in severe winters, and two or three layers of mats may be also necessary over the lights and cloches if very hard frosts indeed prevail.