82 HORTICULTURE BY IRRIGATION. 



can be planted than by the first method, but it is more difficult and expen- 

 sive to operate. 



Before beginning to put the seed in mark the ground off in 

 straight rows, from three and one-half to four feet apart. Plant the seed 

 about eighteen inches apart in the rows. 



If the ground is weedy it is best to harrow just as the plants are com- 

 ing up. If they are free from weeds, start the cultivator as soon as the 

 potatoes are well out of the ground and cultivate deep and thoroughly. 

 This will keep the ground loose around the plants and between the rows. 

 If weeds come in so close to the plants that they cannot be covered or 

 rooted out with the cultivator, then it will be necessary to go through 

 with hoes and cut them all out, as a crop of potatoes and weeds cannot be 

 successfully raised at the same time. 



IRRIGATION. 



All potato growers agree that the longer the vines can be kept grow- 

 ing without irrigation, the better for the crop; but when they begin to 

 wither and turn yellow around the roots, it is time to water them. When 

 this condition is observed, furrow the rows out with the shovel plow with 

 wings attached. Make deep channels so that the water will not run up 

 around the vines, and also arrange so that the lower ends of the rows will 

 not be flooded. This is an important precaution, as permitting the water 

 to flow over on the plants would prove fatal to them. With right man- 

 agement two irrigations are all that is necessary to raise a crop, and 

 frequently one watering will be sufficient if applied at the right time. 

 As soon as the ground becomes dried so that it will not be sticky in work- 

 ing and before it has time to bake, cultivate the soil up loose and deep as 

 before. The crop in Colorado matures usually about October, when it is 

 ready to be dug. 



HARVESTING. 



No successful potato-digging machine has yet been introduced, but 

 one or two have been tried that do fairly well, and work much faster than 

 by hand if the soil is moderately dry at the time of harvesting. Until 

 these machines are perfected, which they undoubtedly will be in time, the 

 potato fork will be most generally used. Some growers use the plow, but 

 with indifferent success. 



If the crop is to be marketed at digging time, the best method is to go 

 along the rows and pick up the merchantable potatoes first, and after- 



