Our beloved Yucca plant has been dropping its branches quite a bit, the leaves seem ok but the branches that were fully upright now becoming almost horizontal, stem feels like hollow towards the tips. A few months ago we had fungus gnats problem and we drained the plant for a few months then applied a bit of soapy water, neem oil solution. Fungus gnats seem to be gone and it was happy but last few weeks this started to happen. Do you recognise why this happens? Do we need to repot it? any guidance much appreciated.
The plant probably sustained some degree of root rot at the time the fungus gnats were present. Assuming the soil was not allowed to go excessively dry while draining the soil then it's likely that the plant is still afflicted by root rot. Is it possible for you to check on the condition of the roots? It may be a challenge because of the size of the plant but perhaps you can place it on its side and gently ease the root ball from its container.
Also check for an even moisture level throughout the root ball while doing so. Hydrophobic areas may have developed in the soil if it had been allowed to go dry for too long.
