34 POPULAR VEGETABLES 



sufficient quantity must be used, but lifted roots are 

 not so productive as older ones in permanent beds. 

 Give rather more warmth for the December forcing, 

 and a few days' longer forcing may be needed, but 

 after that, if the batches are placed indoors every 

 three weeks, there will be a full supply. For the early 

 batch bottom heat such as leaves and litter may be 

 used to force up the growth. Asparagus for later sup- 

 plies may be grown in frames placed on a good bed 

 of slow heating materials, covering the glass well at 

 night to maintain an even temperature. The removal 

 of roots to frames rilled with fermenting material is 

 a simple matter, and Asparagus grown thus, that is, 

 near the glass, is better than that from hothouses. 

 Market growers force old roots. Deep and wide 

 trenches are dug out, fresh manure is placed in them, 

 and then the roots. Frames are used, and manure 

 is used freely outside them. 



A much better system of forcing, however, is to 

 use hot water. It is costly at the start, as the pipes, 

 boiler, brickwork and labour must be taken into 

 account, but it is money well spent when the cost 

 of lifting roots for forcing, and manures, and labour 

 are considered. When hot-water pipes are used, beds 

 need more moisture, as they dry up quickly, both in 

 summer and during the forcing period, so that in 

 forming new beds an efficient water supply should be 

 arranged for ; indeed, if the beds can be flooded so 

 much the better. From May until the end of August 

 the plants must make a liberal top growth, and without 



