Question
I purchased 2 Peace Lillies from the same source...about 2 weeks apart.  Both of them are now getting black spots all under the leaves.  It's mostly the lower leaves.  After the black spots appear, the whole leaf will turn yellow.
I also have other Peace Lillies at home in the same location that have no problem.  These plants have been in my home longer.
What is this black spot and what can I do?  I cut all the leaves off, but more keep happening.

Thanks!
Crystal

Answer
Crystal,

You may have an insect called scale. Let me know if the black spots are small and see if you can dip a Q-tip in rubbing alcohol and flick them off the leaf. If so it is scale.

Go to a garden center and ask for Neem oil for plants ( I now Lowes carrys it) and mix it with water according to the package instructions then put the mix in a spray bottle and spray the fronts and backs of all the leaves well. Repeat the spraying every other day for 2 weeks to kill any eggs that hatch. If you can't find Neem oil spray with rubbing alcohol straight out of the bottle in a spray bottle and use the same spray schedule.

Persistence is the key to getting rid of these pests. One spraying will not work. That should get rid of the problem. You will need to watch it closely in the future for signs of scale and check your other plants also. They seem to be becoming  a worse problem in the last few years.
I fight them frequently myself. Good luck.

Darlene

PS If that is not the problem the onlyother thing your black spots could be is a fungul problem. Write back and let me know if you are eeping this plant indoors and if you have children or pets and I will tell tyou how to treat it. I would get the sick peace lillies away from the others ASAP.