Question
Hi Jim,

I recently moved from Stockton to Fremont (about a month ago) and I noticed that the several of my cymbidium leaves turned yellow. The cymbidum plants had about 4 hours of morning sun in Stockton. Unfortunately due to a lot of shaded tress at my new place, they only get a maximum of 2 hours of morning sun in Fremont. Would this be the reason for the leaves turning yellow or could it be something else? I always thought that the lack of sunshine makes the leaves turn deep green and not yellow. Please help.

Answer
Hi Yolanda,

Yellowing of leaves is probably not due to the amount of direct sunlight exposure they are getting but it could be contributing to it.  Moving from Stockton to Fremont, there is a difference in the growing environment for the cymbidiums such as humidity, air movement, temperature, etc.  If you are watering on the same schedule as in Stockton, that may be too often because the pot media does not dry as quickly between waterings.  Also, along with this, if you are watering them from overhead with a hose, water may be collecting at the base of the leafs and not drying before nightfall and thus causing some fungus growth.  

To help minimize this problem, look for an area in the yard where there is normally good air movement along with a fair amount of sunlight avaiable.  Water when the potting media becomes barely moist.  There is little danger of frosts in Fremont but be wary of any predictions of night temperatures below 40F.  

Hope this has helped.

Jim Kawasaki
San Jose, Ca.