Thanks for all of the advice, everyone! Millet, do you recommend foliar or root feeding of Epsom salts?
Joe, I am zone 8a, but my trees stayed outside most of the winter, only going inside our unheated garage a handful of times when the temps dropped. The funny thing is, my eureka and Genoa lemons are all dark green, but my Bearss Lemon and Santa Teresa lemons are suffering. I will apply the Epsom salt mix tomorrow and see how it goes. I’m thinking of sending my soil off for testing, too. Just to be safe and on the lookout for future issues.