220 SCHOOL AND HOME GABDENS 



smaller boxes, may also be used, but they give greater 

 difficulty in regulating moisture. The same may be said 

 of the " flats " used by florists. Zinc trays about three 

 feet long, one inch deep, and twelve inches wide should 

 be provided. The dimensions of the trays may vary, 

 depending upon where they are to be used. They should 

 be constructed so that they may be used on the window 

 sill, either inside or outside of the window. 



Soil. A soil prepared by mixing two parts of garden soil 

 with one part of manure and one part of sand will be 

 suitable for germinating seeds in window boxes. Before 

 the materials are mixed, they should be sifted through 

 a screen with a quarter-inch mesh. After mixing thor- 

 oughly, add water, a small amount at a time, and work 

 the soil with the hand or with a garden trowel, so that 

 all parts will become equally moist. The amount of 

 moisture added should be such that the particles will 

 fall apart slowly when a handful of the soil is pressed 

 lightly together. Prepare a quantity of soil so that it 

 will be ready for use. 



Drainage material. Some coarse material must be 

 provided for drainage. Broken pieces of flowerpots, 

 crushed stone, small cinders, and fibrous pieces that will 

 not pass through the screen easily will serve the purpose. 



How to plant large seeds. In the bottom of the box 

 place about an inch of drainage material. Then fill in 

 soil so that the surface is within two inches of the top 

 of the box. Push the earth well into the corners of the 

 box and make it smooth and level with a piece of board. 



