TEMPERATURE 



Adverse temperatures are among the most detrimental of all factors 

 encountered in growing plants in the home. The night temperature is 

 much more critical than day temperature — likewise, plants growing in 

 sunny windows or strong light can stand higher temperatures than the 

 same plants growing in poor light. Only the toughest house plants are 

 able to stand a combination of temperatures of 70° F and above, and 

 poor light conditions. Fig. 2 shows a normal cyclamen plant compared 

 to one grown at a high temperature with poor light. 



Fig. 3a (left) — A special container for starting tiny seeds 



Fig. 3b (right) — Seedlings of many house plants are more easily grown in 

 boxes of soil until large enough for 4- or 5-inch pots 



Other detrimental effects of high temperatures are rapid drying and 

 the accelerated rate of increase of insects on plants, especially thrips and 

 red spider mites. 



PROPAGATION 



Plants are propagated either by seed or from vegetative parts. Many 

 plants that are used in the home do not produce seed under these con- 

 ditions. Some varieties do not come true from seed and other plants are 

 produced from seed with some difficulty. Fortunately, in these cases, 

 there are other ways of propagation. 



Where propagation by seed is possible, plants are usually free from 

 insects and often more vigorous from the beginning. Starting tiny seeds 

 and watching them grow into mature plants afford a particular joy to 

 many plant lovers. A special container for germinating seeds is illus- 

 trated in Fig. 3 A. This apparatus has been used successfully at the Uni- 

 versity of New Hampshire in starting many kinds of seeds under the 

 most exacting conditions. The small porous pot in the center is stop- 

 pered to hold water and is kept full of water at all times. The large pot 

 or pan should be porous; common flower pots are satisfactory. A good 

 house-plant soil mixture, with sufficient organic matter to make it re- 

 tentive of moisture, is satisfactory for starting most seeds. Enough sand 



Six 



