CHAPTER XI 



FORCING AND RETARDING PLANTS 



Nature of the process. In nature each species of plant has 

 its own season of growth and bloom, determined largely by 

 conditions of temperature, moisture, and the like. Man, by 

 regulating these conditions, creates an artificial season, and 

 hastens, delays, or extends the flowering and fruiting period, 

 thus obtaining his vegetables and fruits " out of season " at 

 any time of the year. Hastening the development of a plant 

 is called forcing. This is accomplished by high temperatures, 

 increased moisture, and an abundance of plant food, and results 

 in great succulence and brittleness. Lilies, hyacinths, narcissi, 

 and other bulbous plants are among those that are most 

 easily brought into bloom in this way, either in our homes or 

 in commercial establishments. Owing to the amount of food 

 stored in their bulbs, they may even be forced without soil 

 in which to root, if they are kept supplied with water. On 

 some private estates melons, grapes, peaches, strawberries, 

 cucumbers, and tomatoes are produced in midwinter in houses 

 devoted to this purpose, while the growing of roses, carnations, 

 chrysanthemums, sweet peas, and the like for use in winter is 

 a regular business with the florist. In the vicinity of large 

 cities lettuce, radishes, onions, rhubarb, and asparagus are 

 often grown in this way for the early markets. The business 

 of forcing is carried on under glass in various kinds of houses 

 or shelters, but these all fall under the general heads of 

 greenhouses, cold frames, hotbeds, and hothouses. 



Retarding. The operation of holding back the growth of 

 plants for the production of blossoms later is called retarding. 



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