50 Culture of Pines by Means of Steam 



Art. XII. Some Remarks on the Culture of Pines, and other 

 Plants, useful or ornamental, in Beds heated by Steam acting 

 on a Mass of loose Stones. By John Hay, Esq., Garden Archi- 

 tect, Edinburgh. 



Sir, 



That part of the pit for the reception of the pine-pots, 

 above the cover of the steam vault or chamber, is 20 in. in 

 depth. As the chamber is covered with Arbroath pavement, 

 a kind of stone of a very hard and impervious quality, and a 

 better conductor of heat than some other sorts of stone or 

 tiles, a layer of small cinders, or soft bricks broken very 

 small, 4 in. deep, is laid above the cover. These retain the 

 heat longer, and at the same time act as a drain for carrying 

 off any moisture that may proceed from the bottom of the 

 pots or otherwise. 



You will see from my paper * the reason why the pots of 

 pines at Cunnoquhie had to stand on the layer of cinders, 

 namely, the want of head room for the plants, the pits having 

 been built solely for the growth of melons ; but now that 

 these pits are altered to suit the culture of both pines and 

 melons, the depth of the pit above the cover of the bed of 

 stones is the same in both : for the melons, 4 in. of cinders, 

 and 15 or 1 6 in. of soil above ; and for the pines, 4 in. of 

 cinders, 3 in. of the same substance in which the pots are 

 plunged, and 1 2 in. for the depth of the pots. The edges of 

 the pots of pines will then be one inch lower than the top of 

 the steam-flue. 



Colonel Paterson mentioned to me that he could procure 

 tanners' bark at Cupar for plunging the pine-pots in. This 

 I objected to, as being the worst substance that could be 

 employed for the purpose, as, being of an open nature, it 

 would permit the heat to escape ; but I recommended the use 

 of well rotted leaves, or any free gravelly soil. At Castle 

 Semple, this season, about 1 6 ft. in length of one of the steam 

 pits have been planted, by way of trial, with pines without 

 pots, in a bed of prepared soil, with a view of fruiting the 

 plants next summer. I also recommended Colonel Paterson 

 to do the same in one light of his pits, which I suppose hag 

 been done. Tanners' bark has not been. employed at Castle 

 Semple for plunging the pots in ; in general, it has been well 

 rotted leaves, firmly pressed round the pots. This season, 

 however, two small portions of one of the pits have been 

 separated from the rest by boards ; and into the one fine sand, 



* In the Caledonian Horticultural Transactions ; it will be given in next 

 dumber, with correct copies of the engravings. — Cond. 



