The effect of intense hydrofogger use in the greenhouse

[Lars Kurth]

Hi,

I went for a 7 days on holidays with nobody being able to water the greenhouse. To avoid that the orchids would become too dry, I left the hydrofogger on 100% on a timer. The fogger is connected to a water tank, which I was feeding through an RO system. I had the fogger from 4-5 AM and from 8 to 16:00's. In terms of weather, the first 2 days of the holiday were sunny, the rest largely grey, rainy and fairly cold. As a consequence, the plants did get more moisture than I bargained for. And that in somewhat cooler conditions than normal.

When I got back today at 7pm and inspected the greenhouse, some plants were quite wet, indicating that the fogger regime created too much moisture (when it is on, it creates a dense mist, which if the weather is not sunny soaks mounts and the top inch or so, of the growing medium in pots.

Here is what has happened.

1) Most plants have gone into an absolute riot of growth. Practically all Vanda's and Angraecous plants have started to rapidly grow both in terms of leaves and new root growth. The same is true for my Dendrobiums, Cattleys & co, which have thrown out masses of new roots. Some roots have grown 2 cm's in a week!
2) Nothing has rotted or been damaged.

The lesson to take away is that simulating a few consecutive rainy days in the greenhouse, can have an incredible effect. The effect of the fogger essentially compares to a few hours of light but persistent rain in a cooler environment. I would guess that using the fogger this way, but maybe more carefully (maybe limit the usage of intense fogging to 2-3 days in a go and then switching to a drier regime) may be extremely beneficial.

I'd be interested to hear your views. Will experiment a little with the fogger during the summer and keep you posted.

Lars