Q.Californian Lilac Tree
Hi had it since March it was very green and flowering. Over last few weeks it starting developing yellow leaves which fall off. I have it in a very large Dobbies plant pot sat on soil topped with wood bark. I’ve read about under and over watering. Problem only started since extreme heat. This tree is so important to me as the soil contains my late husband’s ashes. I would be so upset if it died.
(1) You need to check for over-under watering since the problem started in the summer months.
(2) FYI: I am aware that human cremation ashes contain toxic levels of salts for some plants and lack other minor micronutrients. I am not sure if that might account for the yellowing. If I were to add ashes to a potted plant, I would spread a tiny amount of ashes. Otherwise, i would scatter them, bury them, store them (at home) or send them to the moon with Celestis/Elysium/etc...