I have a garden full of agapanthus and after they flower in december/january they nearly all die and just look terrible. We always have a grasshopper problem just after the flowers die and I use a homemade spray to get rid of them and I pull off all the dead and damaged leaves....but now (april/may) the plants all look droopy and just plain unhappy. I have agapanthus in another garden opposite these ones and they are happy and healthy. I thought these plants were hardy? I'm thinking it may be a drainage problem?