Expert: C.L. Fornari - 7/11/2011

Question
Hi, My husband bought me a Petunia plant. The problem Im having is my Petunia is dying. I dont know why. It has direct sunlight. It gets plenty of water. It was doing real well for awhile. The leaves are turning yellow and hard. I dont know what Im doing wrong. It is in a pot.

Answer
Heather,
Be sure you're not overwatering. Yellow leaves can be a sign of root-rot, caused by too much water. In general, petunias should be watered well when dry but then not watered again until the soil feels dry on the surface.  Another way to judge is to learn how heavy the pot feels when the plant is wet and wait to water when the pot feels light. If you think it might have been kept too wet, clip some of the stems in half right now and let the soil dry a bit. (Not until the plant wilts, however...check soil daily to see if it feels dry.)  After watering again, give the plant some fertilizer mixed according to the directions. (You could also use a time-release fertilizer that is in the form of little beads - use these at the rate recommended on the package.)

If you see the plant revive in response to this treatment, wait a couple of weeks and then prune back another four or five stems to prompt new, bushy growth. Continue with this few-stems-at-a-time pruning until the end of August.

Do the remaining green leaves look clear and green? No sign of whitish or grayish powder on them?  If there is, you might have mildew which is a fungal disease.  If it has a fungus it would be better to thank the plant for coming and toss it out rather than trying to treat the problem.

all the best,
C.L.