What is the correct humidity for hibiscus in the greenhouse?

[Louis]

Charlie et al,

I am keeping a constant temperature of 70 - 75 degrees in the greenhouse. and it might go up to 85 on a sunny day.
I have a humidifier that will add moisture to the greenhouse when needed. on a sunny day or dry night, i can get the humidity up to 80%.

What would be the ideal humidity for the hibiscus. so far they like the moist environment. i don't what it too high to cause mold or other problems.

if i left the greenhouse to its own design without the humidifier, it might be as low as 30-40 percent.

thanks,

louis

[Doll]

I don't think the high humidity will be a problem at those temperatures as long as you have good air circulation. The plants like the higher humidity and it will prevent spider mites.

[Charlie]

Most studies on this have found humidity over 90 percent to be a problem, bringing more disease to the plants. I've found that 60 percent works well for me and avoids drip problems from the ceiling better than higher humidity. I wouldn't go over 80 percent in your greenhouse and I think you will find anything from 50 to 80 percent will be good for the hibiscus.

Of course some places near the Gulf of Mexico often have humidity close to 100 percent but there is also a breeze a lot of the time. Definitely moving the air around helps with disease problems.

Charlie

[Louis]

thanks charlie and doll.

lou