318 CALIFORNIA VEGETABLES. 



all the thermal belts at different elevations on the hill- 

 sides both on the Coast Range and the Sierra Nevada, also 

 on the warm interior plains, but not usually on the river 

 bottoms nor on the low places in small valleys. Owing, 

 however, to the partial resistance to frost of the potato, 

 there are very wide areas both on the coast and in the in- 

 terior of central and southern California, where the fall 

 growth of potatoes is safe and worth wider attention than 

 is given to it by home gardeners. Where irrigation may 

 be had to start the seed well the fall rains usually carry on 

 the growth. 



Planting for what may be called the second run of new 

 potatoes requires stricter attention to thermal conditions. 

 This crop must be growing in December and January, 

 which are our months of heaviest frosts and rainfall usu- 

 ally. Strictly thermal belts, to be found at different ele- 

 vations on hillsides, generally within the reach of ocean 

 influences in the south half of the California coast line, 

 but also here and there on the hillsides of the interior, 

 favor the growth of the potato all through the winter, if 

 the soil be light and kept warm by free escape of surplus 

 water and abundant winter sunshine. 



The third run of new potatoes is secured by the plant- 

 ing of the early varieties as soon as possible after the 

 heaviest frosts of the locality are over, and the soil be- 

 comes warm enough to push growth. This is the main po- 

 tato planting season of California, and covers a wide range 

 of dates, beginning with January on light, well-drained 

 soils at the south to get the earliest new potatoes for East- 

 ern shipment in May ; proceeding in February, not only in 

 the south, but on warm uplands all through the central 

 portion of the State, and continuing with planting all 

 through March, April, and May, as favoring soil condi- 

 tions come successively to the upper coast valleys and the 

 mountain regions, or as the river lowlands and reclaimed 

 islands are drained of their surplus water. In fact on in- 

 terior river lands planting may be done as late as June and 

 July and the crop comes on rapidly with ample heat and 



