Problems with a guava tree in greenhouse

Question

I have a guava tree growing in a greenhouse in Colorado. It was planted as a small (about 15″ tall) plant last spring. It has grown well; however, through the winter months the leaves have turned a dark black color and there appears to be brown spores on the leaves. Can you suggest any solutions for this plant? We had a month or so of some very cold nights with the greenhouse dropping to about 43 degrees F. Any advice for growing a tropical plant indoors would be very much appreciated.

Thanks,
Laura

Answer 1

Guava do not survive freezing temperatures though they can do ok with a brief dip in temperatures, an extended time in the cold may kill off the tree. If the roots survive, the tree can grow back but it may take some time.
The black leaves are likely due to the cold exposure.
Here is a link to refresh you on the care of the tree.

https://www.gardeningknowhow.com/edible/fruits/guava/growing-guava-fruit-trees.htm
It's possible the spores you are referencing are a disease.
You can use the links below to reference the description.

http://edis.ifas.ufl.edu/pg133
http://vikaspedia.in/agriculture/crop-production/integrated-pest-managment/ipm-for-fruit-crops/ipm-strategies-for-guava/guava-diseases-and-symptoms