366 VEGETABLE FORCING 
for winter forcing, but the spring crop does very well in 
solid ground beds. 
The soil for eggplants should be sandy if possible and 
well enriched with rotten manure. This plant makes the 
most rapid growth and produces the largest fruits when 
the soil is filled with decaying vegetable matter. 
The eggplant does not need a large amount of water. 
It thrives best when the soil is only fairly moist. 
No trimming or tying is necessary, but the pollination 
of the flowers must have careful attention. The fruits 
set without being fertilized, but they never develop to 
edible size. Hand pollination, as explained for melons, 
page 352, is most thorough and unquestionably the best 
method for winter eggplants, but bees (page 332) are 
satisfactory for the spring crop. 
The eggplant is subject to the attack of most of the 
greenhouse insect pests, and only constant vigilance will 
prevent serious injuries. 
KOHL-RABI 
A few greenhouse growers have tried kohl-rabi (Fig. 
129), and some report-that the profits are at least fairly 
satisfactory. The plants are started in the same way as 
cabbage. Seed may be sown in beds or flats and the 
plants at three or four weeks of age pricked into flats. A 
month later they will be ready for the ground beds, or the 
raised benches. Six to 8 inches between plants will pro- 
vide space for the development of good roots. White 
Vienna is an excellent forcing variety. The tender stems 
are of the highest quality. 
MINTS 
The different kinds of mint, especially sage and spear- 
mint, are easily grown in greenhouses which provide 
about the same conditions of heat and moisture as are 
