THE ORCIIII) WORLD. 



[April, 1914. 



ORCHIDS FOR AMATEURS. 



THE month of April marks the armal 

 of the most favourable growing" 

 conditions for orchids of the cool- 

 house section. The artificial heat that was 

 found so necessary during the recent winterly 

 months may be almost dispensed with, only 

 on cold nights will an\- be required. No 

 attempt should be made to maintain a high 

 night temperature by closing the top venti- 

 lators. A light and buoyant atmosphere can 

 be produced by keeping a little heat in the 

 pipes, just sufficient to cause the air to be 

 continuall)' in circulation. 



Frequent damping down of the house will 

 be required on all fine days, and even when the 

 weather is dull care must be taken that there 

 is sufficient atmospheric moisture. Odonto- 

 glossums, as well as most other plants of the 

 cool-house section, should not be exposed to 

 currents of dry air ; they can never be 

 successfully grown when placed near a 

 ventilator that admits dry air from outside, 

 or in proximity to the hot-water pipes when 

 they are in use. 



At the present time a moist and genial 

 atmosphere is required to encourage the 

 plants to make rapid and vigorous growth. It 

 is only when the bulbs have finished their 

 season's growth and require ripening that a 

 drier air is needed. Amateurs who have 

 recently commenced the cultivation of orchids 

 expect some definite directions concerning 

 the exact time that the plants are to be 

 watered, and how often the house should be 

 damped down. These questions can only 

 be answered after a careful consideration of 

 the weather ; those growers who can best 

 judge the coming atmospheric changes will 

 reap the most success. With a changeable 

 climate precaution is always necessary. 



In the Cattleya house rapid growth is 

 being made ; every advantage must, therefore, 

 be taken of sunny days to encourage a robust 

 nature and a healthy state of the new bulbs. 

 On bright days the sun causes the temperature 

 of the house to be considerably higher, which 

 results in a large amount of moisture being 

 taken up by the atmosphere. Towards the 



evening the lowering of the temperature 

 causes some of this moisture to be iDrecipi- 

 tated in the form of dew, and if there is a 

 considerable fall it is not unlikely to result 

 in some damage, frequently a chill being 

 given to the plants. 



Sunny da\'s frequently bring clear and 

 chilly nights ; the coldest nights often follow 

 the brightest days. Consequently, it becomes 

 very necessary to utilise sufficient artificial 

 heat at night time to prevent a serious drop 

 in the temperature. The night temperature 

 should always be lower than that existing 

 during the day time. In winter, and also 

 during dull weather, a difference of from 

 5-10 degrees may be aimed at, but at other 

 times of the year, and when the day 

 temperature rises as much as 25 degrees by 

 sun heat, then the night temperature may be 

 from 10-15 degrees less than that of the day 

 time. An average temperature of 65-75 

 degrees by day time and 60-65 night will 

 prove very suitable for the majority of 

 Cattleyas, Ljelias, and their hybrids during 

 this period of the year. 



The shading used on the Cattleya house 

 should never be of a permanent nature. 

 During the early morning the full benefit of 

 the sun may be obtained without any danger 

 of the plants being scorched, and, what is 

 perhaps more important, the temperature is 

 rapidly raised to a beneficial degree, and thus 

 gives the plants a much longer growing-day 

 than when permanent shading is used. 



The blinds need not be used until the 

 leaves feel warm on being touched by the 

 hand. If shading is neglected, the leaves will 

 rapidly become hotter and eventually be 

 severely damaged and blistered bv the heat 

 of the sun. 



To grow Cattleyas really well, and equal to 

 the best specimens seen at exhibitions, 

 considerable attention is required to let the 

 plants have as much light and warmth as is 

 possible without them being damaged. The 

 amateur who is likely to be away from his 

 houses for several hours should take the 

 precaution of letting down the blinds before 

 leaving, for should a few minutes' bright 

 sunshine appear during the middle part of 



