Q: The attached photo, kindly sent to me by a friend who checks my house while we are away for the summer, shows my euphorbia houseplant with drooping stalks. I have been researching online, to no avail. As of a week ago, he said the plant still appeared green in color.
A:Β Euphorbias should be treated much like cactus. They need well-drained soil and can suffer from fungal diseases if left in too much water for too long. Your plant is showing signs of a vascular problem in that it cannot provide enough water pressure to keep some of the stems upright. Wilting like this can be a sign of underwatering but it can also be a sign of overwatering or disease when the stems are clogged with fungi.
If you can rule out under watering, then consider your container. From your photo, it appears the container doesnβt have a way to drain and if thatβs true, it can be part of the problem. You might try cutting off a wilted stem and look at the cross section to see if it appears to be diseased. It would likely be discolored if it were diseased.
If so, itβs possible you can cut off the infested parts and still have a surviving plant. Be sure to disinfect your pruners between cutting diseased tissue and healthy parts in case it can be spread on your tools. You can use a diluted bleach solution or rubbing alcohol solution (one part to nine parts water).
Once you cut off the diseased parts, the first thing to do is see if your plant container can be replaced with one that drains so any excess water can be diverted from the root zone. If a disease has spread to the main stem, there might not be anything to do for your plant. Time will tell.
Peter L. Warren is the urban horticulture agent for the Pima County Cooperative Extension and the University of Arizona. Questions may be emailed to
