I need advice. I first noticed that some branches of one of my plants (outdoor grow) were yellowing about a month ago. I thought it was a nutrient deficiency, but I’ve been treating it regularly. Then I noticed that the yellowing branches had all developed dark brown spots on the main stem completely surrounding the yellowing branch. These spots appeared first towards the bottom of the plant and have spread quickly. Now, the patches have also developed what seems to be a dark mold. The patches then spread to my other plants and the same thing is happening. Most of the patches are on the main stems of the plant. Anywhere the main stem surrounding a branch stays green, the branch is very healthy. Some of the patches have appeared a little up a single branch and away from the main stem. I have one plant left that doesn’t have any patches on the main stem, just a couple branches affected. The other two plants might be lost causes, but I’d really like to save what I can. Should I cut away the yellowing branches? Is there anything I can do to the affected main stems?