320 CALIFORNIA VEGETABLES. 



is moderate. It cannot give satisfaction unless its mois- 

 ture requirements are met. 



Heavy soils in garden culture can be greatly improved 

 as described in the chapter on Vegetable Soils of Califor- 

 nia. Early and deep working of the soil and the plowing 

 in of rotten straw and compost and thorough mixture of 

 these materials through the soil will have marked effect, 

 but heavy land potatoes seldom have the beauty and flavor 

 of the product of the light, rich loams. 



Culture. Deep working of the soil is essential in pre- 

 paration for potatoes as has already been urged for beets 

 and other root crops. The soil must be made mellow to a 

 good depth by at least two plowings and kept mellow by 

 subsequent cultivation. 



Unless the seed potatoes are old and show active eyes, 

 they should be exposed to sunlight for several weeks to 

 advance germination. This is especially the case when the 

 tubers of an early crop are used for later planting the 

 same season. 



All proposed methods of seed-cutting have been tried in 

 California, and each has its advocates. When the soil and 

 season favor, excellent crops are grown from small po- 

 tatoes used as seed, but generally the selected fair-sized, 

 merchantable potatoes, cut into quarters lengthwise, pro- 

 duce best results. Cutting should not be done too long 

 before planting, to guard against too great drying of the 

 seed. Recently machines for seed potato cutting have 

 been used with satisfactory results by large planters. Dis- 

 tance between pieces in the furrow depends upon the ten- 

 dency of the potatoes to grow too large. This is often 

 corrected by dropping more thickly. The range is from 

 12 to 20 inches usually. 



In the field much planting is done with the plow by 

 dropping the ' ' seed ' ' in every third or fourth furrow, so as 

 to bring the roots about three feet apart, and covering 

 with the following furrow. Depth of planting depends 

 upon season and soil as described on page 158, the same 

 principles governing as in the planting of seed. After the 



