Ask a Question forum: White mold on indoor lemon tree

Views: 129, Replies: 5 » Jump to the end
San Francisco, CA
Feb 3, 2018 1:08 PM CST
Hello! My indoor lemon tree has developed this white, powdery/Cobb web-like mold.

Do you know what this is, what's causing it and how best to treat the plant?

Thank you!
Thumb of 2018-02-03/Corinnebright/a70f3b

Thumb of 2018-02-03/Corinnebright/96718c

Thumb of 2018-02-03/Corinnebright/c32dfe

Name: Carol
Santa Ana, ca
Sunset zone 22, USDA zone 10 A.
Charter ATP Member Hummingbirder Lover of wildlife (Black bear badge) Orchids Region: California Plant Identifier
Feb 3, 2018 3:06 PM CST
I see Mealy Bugs. They can be removed /killed by wiping them off with Alcohol wipes or Q tips dunked in alcohol. It's hard to see them or get to them in the crevices, so be persistent until it's all free of them or the babys will hatch.
Feb 3, 2018 3:28 PM CST
Hi there those are Mealybugs you can see on the leaf of your indoor lemon tree. I had some of these on one of my cactus a couple of years ago. You can Wipe them off. I bought some special mealybug killer and that got rid of them for good just check you can spray your lemon tree with the mealybug killer. Hope this helps
Name: Daisy I
Reno, Nv (Zone 6b)
Not all who wander are lost
Garden Sages Plant Identifier
Feb 3, 2018 9:43 PM CST
Those are the nicest photos of mealybugs and mealybug nurseries I have seen for quite awhile. Do we have a bug ID spot to put them?

Insecticidal Soap (make sure you soak every surface) is a good defense for mealybugs but this is not a short term fight. Be persistant. Mealybugs are small enough to hide in the pores of pots, the grain in wood surfaces and in nooks and crannies of your tree. It will be a battle eventually won but...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost

Name: Will Creed
Professional indoor plant consultan
Feb 4, 2018 12:12 PM CST
Mealybugs, for sure! Mealybugs can be treated successfully and permanently if you are willing to give a really thorough treatment initially.

The juvenile mealies, called crawlers, are translucent and very difficult to see. They also hide in tiny crevices where leaves attach to stems. That is why wiping is never successful and requires repeated treatments regardless of what you use. If you miss a few crawlers, they will reproduce and the infestation will return.

My recommendation is that you mix 5 parts water, 1 part alcohol and a squirt of liquid dish soap. Then, spray all leaf and stem surfaces until they are literally dripping wet. The solution needs to wash over the entire plant so that it makes contact with all of the nearly invisible crawlers. This is a very messy task requiring floor coverings. However, if you are really thorough, one treatment is all that is usually required. I have done this many times successfully so I know it works. I hate having to do it, but I would rather do it this way once rather than having to re-visit the problem again in a month or two.
Will Creed
Horticultural Help, NYC
I now have a book available on indoor plant care
San Francisco, CA
Feb 4, 2018 2:35 PM CST
Thank you all so much for your expert advice! Now to take action!

« Homepage
« Back to the top
« Forums List
« Ask a Question forum
Only the members of the Members group may reply to this thread.

Member Login:



[ Join now ]

Today's site banner is by ge1836 and is called "Blanket Flower Amber Wheels"