RYERSON EXPANSIBLE ORCHID FOLDER Page L. 
LET'S TALK ABOUT WATER AND HUMIDITY FOR CATTLEYAS 
“How often shall I water my Orchids?" continues to be the most frequently 
asked question. It also is the most difficult to answer. There is only ONE 
answer: "Whenever they need watering," and I don't blame you if you feel that 
is worse than no answer at all, 
But how can there be any more specific answer from someone who has no way of 
knowing the conditions under which you are growing your orshids? To cite two 
extremes in climatic conditions: if you live where there is heavy dew at 
night, and the fog rolls in every morning; obviously your Orchids will need 
less watering than those of Mr. Jones who lives on the arid plains. 
Other influencing factors are the amount of light and air in your greenhouse. 
Are most of the plants grown in pots or baskets? Are the plants crowded or 
widely spaced? How tightly do you pack the osmunda, and how high in the pot? 
At what stage in their growth cycle are the plants in question? 
On Pages G and H, I discussed the growth cycle of Cattleyas and gave you six 
suggestions about how to judge whether or not your plants were reseiving suffi- 
Gient water. 
Since more damage is done to Cattleyas by OVER=watering than by any other 
single mistake, let’s forget the plant for the moment, and consider the osmunda 
in which it is growing. One of the major functions of this osmunda is to en= 
able you to control the moisture available for your plant. If the moisture 
content of the osmunda is properly controlled, the plant will be healthy and 
Vigorous. If the osmunda is kept too wet, it decays, breaks down and the 
plant suffers. It is vitally important to avoid this, because, by the time 
the plant itself shows the effects of faulty watering, great damage already 
has been doneés 
For example, that soured, decaying condition of the osmunda may have caused 
the roots of your plant to rot off. The first evicence of this that you see 
in the plant is the shriveling of the bask bulbs. The inexperienced, think~ 
ing the shriveling was caused by lack of water, is apt to do exactly the wrong 
thing, ie, pour on more water. 
Frequent examination of the osmunda in the SAMPLE MOISTURE POT, as suggested 
on Page H, would have helped you avoid over=watering, before it was two 
late. You can seldom judge the moisture content down in the middle of a pot 
by feeling the surface of the osmunda. It may feel quite dry, while the mid-= 
dle portion actually contains ample moisture. 
Of course, you should not go to the opposite extreme and keep the osmunda so 
dry that it shrinks away from the sides of the pote The ideal condition, 
when the plant is in active growth, is for the osmunda to be uniformly damp, 
but still springy and firm in texture. 
There are two methods of applying water to Cattleyas: 1. Pot watering. 
2e Spraying of foliage and outsides of pots. 
When the experienced grower says he "waters" his Orchids about once a woek, 
he means "pot watering." You may drop in on him several mornings during the 
week, find him with the hose in his hands, and assume he has deceived you. 
Actually, he was only spraying the foliage, which he does not consider 
“watering.” 
