244 CALIFORNIA VEGETABLES 



In the field much planting is done with the plow by dropping 

 the "seed" in every third of 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 in 

 Chapter XI; the same principles governing as in the planting of 

 seed. After the seed is plowed in to a depth of four to eight inches, 

 according to season and soil, a thorough cross-harrowing should 

 leave the field in good shape. On light soils disposed to be dry, a 

 light rolling may be beneficial. As soon as the plants appear, har- 

 rowing with the rows mellows the surface, kills the small weeds, and 

 does not hurt the potatoes. Cultivation between the rows should 

 soon follow and the surface should be kept loose until the plants 

 are quite high. Good, clean culture is the rule with potatoes. In 

 some soils, not disposed to dry out too rapidly nor to crust, crops 

 are often made with little cultivation after weeds stop growing, 

 especially where the plant has the benefit of coast influences, but 

 cultivation for moisture retention, where needed, must be more 

 thorough. 



On lands subject to excess of moisture, winter growth of po- 

 tatoes can be facilitated by the ridge planting described in Chapter 

 VII ; but where this is not likely to occur, reasonably flat culture is 

 best, both in winter and summer. Where potatoes are to be irri-' 

 gated a slight moving of the soil toward the row, so as to make the 

 interspace a little hollow to carry water, is admissible, but "hilling 

 up" must not uncover the firm soil and expose the roots to too 

 great heat and drought. Too high a ridge is also likely to bring 

 the tubers within reach of the moth from whose eggs come the 

 potato worms. During the latter part of the growth the tuber 

 should be well covered with soil. 



Irrigation. The potato should be kept growing thriftily from 

 start to finish. If growth is arrested by drought, a new growth of 

 small potatoes is apt to start upon renewal of moisture, to the detri- 

 ment of the crop. The aim should be, then, to keep the soil ade- 

 quately moist until maturity approaches. This is best done by run- 

 ning small streams between the rows, the planting having been 

 arranged for this distribution. As already stated, excessive irriga- 

 tion is decidedly detrimental to the quality of the crop, and extra 

 effort must be made for even distribution of the water. To allow 

 low places to fill up with water is injurious and to allow the water 

 to come in contact with the plant stems is also dangerous. A good, 

 thorough and uniform wetting of the soil is often enough to finish 

 the crop and it is seldom desirable to irrigate after the bloom ap- 

 pears. Thorough surface cultivation should follow the irrigation, 

 for the reasons stated in the chapter on that subject. 



In connection with the irrigation of potatoes it must be borne 

 in mind that many troubles may arise from irregularity in the moist- 

 ure supply of the growing tuber. Sometimes potatoes are planted 

 on ground which is dry underneath instead of being well wet down 



