What causes the leaves on a Geranium to turn yellow?

I have a potted Geranium on my front deck and the leaves are turning yellow. There are new blooms but the leaves look sickly. What should I do? I don't see any pests and I have watered it regularly.

 

I would say either too much water or not enough. Or maybe it's the sun.
Someone that knows what they are talking about will be along soon !!!

 

I'm guessing too much water also. They like to really dry out between waterings.

 

I would guess too much water as well.

 

Do you pick the flowers and leaves off as they die back? Sometimes if you do not pick off the dying flowers the plant will begin to turn brown. Sometimes the leaves just turn brown and die naturally. New ones always come. Mine are in the sun so that shouldn't make a difference. dooley

 

It sound like to much water to me too.

 

We did have several inches of rain in one week, so that's probably it. Thank you.

 

I agree with too much water