50 SOIL STERILIZATION 



of a rich color having good substance, so that they will 

 last. Peas of the highest quality not only fetch the best 

 prices, but sell more readily, and by their beauty and stay- 

 ing powers they are a testimonial to the seller, whose 

 customer is, therefore, confirmed in regard to their merits, 

 and never hesitates to buy again. Get the best and grow 

 the best; none other pays. 



Sometimes a grower will sterilize his soil as for Chrys- 

 anthemums and Carnations. The method of working 

 and the apparatus required for soil sterilization are simple 

 enough, excepting only the steam generator. A box 

 6 ft. long, 3 ft. wide, and 2 ft. high, made so that the two 

 longest sides slip out, will hold about a load of soil. A 

 gridiron arrangement of tubes i)^ to 2 in. in diameter is 

 required for the inside. Each of the three pipes is closed 

 at the end, and perforated with 2-in., and placed alternately 

 at right angles, that is, eight holes to the foot. The grid 

 should be i ft. shorter and i ft. narrower than the box it 

 is to be used in. A flexible metal tubing to connect up 

 with the steamer completes the apparatus. 



To use it, the grid is placed in the box, and raised on 

 bricks 5 in. or 6 in. from the bottom, and the soil shoveled 

 in until the box is full. The grid is then connected up, a 

 tight-fitting lid placed on top of the box, and the steam 

 turned on. 



Two important points to remember are to screen the 

 soil first and have it as dry as possible, otherwise the process 

 will take much longer. If a steam pressure of 80 lbs. to 

 90 lbs. per inch can be maintained for twenty minutes, 

 this will raise the whole of the soil to a temperature of 212 

 degrees Fahr., and the " cooking " is then finished. To 

 avoid leakage of heat, cover the whole of the box with 

 mats or sacks. After the soil is fully heated it must be 



