Golden Barrel Cactus Turning White

Question

Hi I have this golden barrel cactus since 3 years now. It was pretty healthy and doing good. We have given it a well draining soil. It’s in our east facing balcony. We are in UAE where the weather is above 44 deg centigrade in peak summer. The plant has seen 3 summers so far and has been fine with these. Suddenly it’s started to develop whiteness and looks like it’s dying. We have the same method of watering and nothing has changed. Wondering what to do.

Answer 1

This is a case of roots that remain too wet. They can fight off suffocation for quite some time, being such a tough plant, but will eventually succumb to root suffocation and rot. This is what is happening here.

Likely, with such a large container, the roots have not developed throughout the entire mass of soil. This means that there is a good chance water sits at the bottom of the container.

When repotting, make sure that the new container is only an inch or two larger on all sides. This will prevent too much uncolonized soil. Repot in this manner each time it needs to go up a size. Doing so in small increments, over time, is an easier way to manage soil moisture.

As for now, make sure that your container has holes at the bottom to allow all extra water out. Let the soil dry out thoroughly, AT LEAST down to 3/4 of the entire container or more. Underwatering is much better than overwatering, here.

Fungicides may be necessary. This article will help:

https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm

Using a moister meter with a long probe may be necessary to determine how dry the soil is. This article will help you:

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm

Here is an article for the care of Barrel Cactus:

https://www.gardeningknowhow.com/ornamental/cacti-succulents/barrel-cactus/golden-barrel-cactus-care.htm