RADISH 257 



nearly large enough to market may cause the roots to 

 crack. 



The radish thrives best in a humid atmosphere. Over- 

 head watering, which diffuses a mist over the beds, pro- 

 vides the most favorable soil and atmospheric conditions 

 so far as moisture is concerned. 



Temperature. Too high temperatures produce spin- 

 dling plants and excessive top growth, and the roots will 

 be small. Too low temperatures, on the other hand, 

 cause slow growth and the development of roots that are 

 lacking in quality. A night temperature of 43 to 45 de- 

 grees and a day temperature of 55 to 60 degrees will be 

 found satisfactory. Sixty-five degrees or above on 

 bright, sunny days will do no harm. 



Ventilation. The ventilators should be opened a little 

 every day, unless the weather is unusually severe. In 

 warm, bright weather, air should be admitted as freely 

 as possible. 



Cultivation. Small weeders used between the rows 

 are beneficial in conserving moisture and in keeping the 

 soil in a loose, friable condition. In wide, ground beds, 

 a five-prong welder attached to a long handle, as illus- 

 trated in Fig. 75, will be found a most excellent tillage 

 tool. 



Enemies. The radish, when grown under glass, has 

 very few enemies. As previously stated, damping-off 

 fungi may attack the seedlings in beds that have not been 

 sterilized. The green aphis is the most important insect 

 pest of this crop. It may be controlled by fumigating 

 with tobacco. The radish is more susceptible to injury 

 from tobacco smoke than is lettuce. The safer policy is 

 to make light fumigations rather frequently. 



Frame culture. This is one of the most important 

 crops for growing in hotbeds and frames. (See page 405.) 



Marketing. The proper time to begin pulling the 

 roots depends on a number of factors. If prices are very 

 good it may pay to begin selling them when they are 



