THE FLORAL WORLD AND GARDEN GUIDE. 243 



we must shut tbem up from the variable atmosphere, and conserve 

 for their use as much as possible the natural heat of the earth. la 

 the course of the eight years to which the foregoing particulars 

 refer, the mean difference between the temperature of the earth at 

 two feet depth and the minimuui of the air above tlie same spot on 

 the 11th of January was 10°, the mean of the ground heat bein<' 

 41^°, and the mean of the minimum of air heat 25P. The value of 

 any kind of cover that prevents escape of earth heat without oppress- 

 ing the plants must, on the face of the facts, be obvious. 



It pays well to ibrce rhubarb in sheds and outhouses where the 

 demand is considerable, and there are plants at command for the 

 purpose. The roughest machinery and materials will suffice, and 

 the roots may be packed in any rough stuff that will hold moisture, 

 and as for temperature, it should never rise higher than 60° if 

 supplies are wanted quickly, and a better sample may be grown at 

 an average of ten degrees less. If grown in the dark it will be more 

 delicately flavoured than if exposed to light, while the colour will be 

 scarcely less bright. In systematic forcing for the market, it is a 

 good plan to plant in a well-made bed a lot of the best early sorts, 

 13utting the plants a yard apart, and cover with chimney-pots or 

 large drain pipes, and surround these with hot dung, with a slate or 

 some other rough cover on the top. Rough cradles made in the 

 fashion of crates may be employed for the same purpose, and having 

 been turned over to cover the stools, must be buried in hot dun"', 

 with rather loose and light litter on the top. The plant is so 

 manageable and so profitable that whoever desires a supply of 

 delicate rhubarb from Christmas to May will, after having read this 

 chapter, find it quite easy to devise the means for the realization of 

 the wish. 



The rhubarb supplied to the London markets is in great part 

 forced in tan. The first lot of roots are lifted in October, and are 

 exposed to the weather for about ten days, and they are then packed 

 in tan in a brick pit and very slowly forced. In the course of 

 December they yield a nice supply of most elegant shoots. The 

 second lot is lifted a fortnight after the first, and is also exposed to 

 the weather for a short time, and is tlien packed in tan to give a 

 succession. When the siipplies from these roots are exhausted, the 

 covered stools in the open ground will begin to be productive, and 

 there will be no need for lifting any more roots. It is not necessary to 

 destroy the roots that have been forced, but they must have one 

 year's culture in rich soil to restore their vigour. 



Finally, to maintain the health and strength of the plant, be 

 careful not to remove the stalks extravagantly, for if you pull, pull, 

 pull, with immoderate eagerness, the plant will be seriously injured, 

 and will be very likely to die outright. A short anecdote will illus- 

 trate this point. An amateur who had a fine plantation of rhubarb 

 gave permission to a friend to take as much as he liked while the 

 owner was away for a summer jaunt. The friend was suddenly 

 fired with an ambition to make some wonderful rhubarb wine, and 

 for several weeks in the height of the season, he pulled every stalk 

 he could get, so that when the growing season was over, the stools 

 Aujrust. 



