WATERING AT NIGHT/EVENING

[greg sytch]

I know, I know but as a teacher I have to water at night. I am off now, but beginning Aug I have no choice. I do spray with fungicide and Phyton 20. Is that enough? I notice a little disease here and there, and they are all growing outdoors under shadecloth all year so the air flow is good, but is this enougH? The overall health is ok but I do not want to start something. Any advice? Thanks! Greg in HOT HUMID Tampa Bay

[Lorraine]

Hi Greg,

I would not be watering your chids at night. Sure when it rains at night they get wet but can you set up a misting system on a timer to water your guys in the morning so they can dry off during the day? You could be fighting disease all the time esp if the water sits overnight. I'll even give you some info to set up an inexpensive timed system for outdoors. It's HOT & HUMID here in Boca too. Still waiting for the rainey season. Thought it was supposed to be here a couple weeks ago.

[peter400]

if you have enough air movement and the plants are inside with less humidity i have not had a problem if i only water those that are truely dry. out side, like now in buffalo ny i would wait till morning because it is very humid and not much air movement.

[Ross]

I sometimes have to water certain orchids late in the day. I avoid any that need to be dunked (such as mounted orchids) and avoid getting any water in the crowns of Paphs or Phals. But generally I think it is safer earlier in the day. But you know what? If you can't water early, then water later. This is better than no water at all. Just be careful. I would consider running a fan across the orchids for a couple hours to assure evrything's dried off before going to bed. Just a thought.

[kavanaru]

I normally water my plants in the late afternoon (sometimes even late night) as I normally have no time during the day. I only try to ensure that there is enough ventilation (or in winter, as I grow indoor, the relative humidity in the air is quite low). Furthermore, even if I try to avoid watering the crowns of Paphs and Phals, if this happens I just dry them out with a tissue... so far no problems with my plants...

[Des]

I have never had a problem watering my cymbidiums at night provided the night temperature stays above 15 degrees centigrade. Lower than that and you stand the risk of fungal infections. So if I find it necessary to water on a cool night I water the pot only and try my best not to wet new growths or emerging flower spikes.
This whole question of watering at night has been fascinating to me as there is a lot of misinformation out there on the subject. Plants growing under shade cloth are subject to rain at anytime,day or night. And yet we see so little in the way of fungal and bacterial infections after rain. One has to ask yourself the question , why this is so, just what is the difference between rain water and the water we use on our plants?
After some investigation and experimentation I came to the conclusion that the difference is quite simply dissolved oxygen (O2) in the rain. And further, if that rain is from a thunderstorm then it is possible that the rain contains a tiny amount of hydrogen peroxide. (H2O2) I believe this is possible because of the ozone (O3) generated by the lightning. I have little doubt that this is natures way of keeping pathogens in check in the soil. And this is the reason you will notice plants have a growth spurt after rain
However, what does this all mean for your orchids growing under shade cloth? Rain disinfects your pot plant whereas the tank or tap water is very low in dissolved O2 and won't do the same job. It is for this reason that I have been aerating my nutrient water and adding H2O2 , for some time now , it makes a big difference in the health of my plants

[Gin]

I talked to Andy of Orchids on a Stick at a show , he waters at night in the summer and in the am . in the winter , most of his are mounted in Ca. in shade houses , guess it would depend on where you are located , and how you grow them . Gin

[camille1585]

As I don't have a choice with school/work, I water mine late afternoon-evening. I just make sure to avoid wetting the leaves, since any problems would most likey come from wet leaves rather than wet roots! So far I've not had any problems on any of my orchids due to this watering habit.

[epiphyte78]

Here in dry Southern California I use the predicted minimum temperature to determine when I water.

Basically, when the minimum temperature is going to be mid 40s or below I water first thing in the morning so the plants are mostly dry before evening. As the min temps gradually get higher I water progressively later in the day. When min temps are 55 or above I water at night to maximize the amount of time my orchids stay hydrated. All my orchids are mounted under 50% white shade cloth...so they dry out considerably faster than potted orchids would.

What Des wrote was interesting as my orchids also respond particularly well to our highly infrequent rains...which mainly occur during our coldest months and often at night. The science of it is over my head, but several months back Andy Orchid on a Stick told me that water quality can improve cold tolerance. I was a bit incredulous because I generally equate cold and wet with rot but what Des wrote seems to support the validity of the observation.

[Chococatte]

I can understand those early more hours going to work. I would water the orchids soon after your arrival home in evening. Don't let water sit in the crowns of Pal and Phal these are prone to crown rot.