Though the covering of hot-houses has been already practised in some cases, I am not aware of any one having adopted a close covering with the view to facilitate ventilation or aëration during the night. It appears to me that the circulation of air, secured by the means here proposed, would have much influence in excluding cold, whilst at the same time it would prevent the interior from becoming too warm and close.
_On Transplanting and the use of Turf Pots._
I have, at p. 26, given what appear to me to be some of the principal reasons against the practice of transplanting, or planting out, Cucumber and other plants. When this is done after any quantity of roots are produced, some injury or check must be sustained during the process; and checks of this kind are opposed to the realisation of the greatest results within the shortest period, which of course is the great object in view. Where it is inconvenient to plant the seeds in the places the plants are intended to occupy, or to put out the young plants during the earliest period of their development, or where propagation by cuttings or layers, is adopted, and the plants of course have to be potted separately, so as to be in a removable state, the following simple plan may be adopted, and will be found to combine all the advantages and conveniences attending the use of pots, with the avoidance of the evils of transplantation, &c. The plan referred to, consists in the employment of turf or peat, so contrived as to supply the place of pots, and which of course at the time of planting is simply placed, along with the plant it contains, at once into the soil, without in the least disturbing the roots, which, growing through the substance of the turf, extend beyond it in all directions into the free soil provided for them. These turf pots are made of spongy, fibrous turf--whether loamy or peaty is not material, provided it is full of fibre, so as to admit of being readily traversed by the roots. The grassy surface is evenly removed, and the under-turves are cut three or four inches in thickness, and are then divided into squares of about three inches across. The centre of each of these little squares is taken out by means of an iron scoop, such as that represented in the annexed sketch; and this is then filled up with soil, and the plant, or seed, or cutting, or layer, inserted as if it were into an ordinary flower pot. It will be obvious that by this plan, every plant is independent and perfectly removable--thus securing the convenience of sowing or planting and rearing the plants in pots during their earliest stages: on the other hand, at the time of planting out permanently, the plant, turf, and all being set carefully into the soil, no check is sustained, because the roots remain undisturbed, and may, as they advance, penetrate through the turf into the prepared soil which surrounds them; in this way the advantages of sowing or planting at the very first in the position the plants are intended to occupy permanently, are secured.