98 One Thousand Questions in Agriculture 



in a hot-bed or cold-frame in February and break off the shoots 

 and plant as soon as you are out of danger by frost. Sweet potatoes 

 are more tender than common potatoes. There are places in Contra 

 Costa county where they do well, though some parts of the county 

 do not have enough summer heat. 



Sweet Potatoes Between Fruit Trees. 



I am expecting to grow a fall crop of about twenty acres of sweet 

 potatoes. The land is a heavy, sandy loam in the interior, which has 

 been set out this spring to almonds, apricots and prunes. I wish to grow 

 sweet potatoes between trees. Would an irrigation every forty days be 

 often enough? Also, if either sivect or Irish potatoes grown betiveen rows 

 are harmful to either of the varieties of fruit mentioned? 



We see no reason why you should not get your crop, providing 

 you do not have to run the plants into the frosty period, and sweet 

 potatoes will not, of course, stand frost as well as the common 

 potato. The moisture which you propose to give ought to be enough 

 for a retentive soil in connection with good cultivation until the 

 vines cover the ground. Growing any crop between orchard trees 

 is apt to be an injury to the trees, because of the spaces which are 

 not and cannot be adequately cultivated, so that the ground around 

 the trees is apt to become compacted either by the run of water or 

 the lack of cultivation, or both. Our observation has been that Irish 

 potatoes are no more injurious than other crops. Any crop will 

 injure young trees if it takes moisture they ought to have or inter- 

 feres with good cultivation of the land. 



Giant Japanese Radish. 



In discussing sakurajima (giant Japanese radish) Eastern publications 

 advise planting late, about August i, and not earlier than July i. What 

 can you tell me about the plant here? 



The Asiatic winter radishes can be successfully planted in Cali- 

 fornia in July or August if the soil is thoroughly saturated by 

 irrigation before digging and planting. It is, however, not so neces- 

 sary to begin early in California as at the East, because our winter 

 temperatures favor the growth of the plant, while at the East they 

 have to make an early start in order to get something well grown 

 before the ground freezes. For the growth of winter radishes, then, 

 in California you can wait until the ground is wet thoroughly by the 

 rain, which may be expected during September, and afterward you 

 can make later plantings for succession at any time you desire during 

 the rainy season. This applies to all kinds of radishes. 



Rhubarb Rotting. 



/ have planted rhubarb roots in the San Joaquin valley and find the 

 root crowns rot below the surface. 



The old-fashioned summer rhubarb usually goes off that way in 

 very hot localities. If there is too much alkali or hardpan, or if 



