I thought my avocado tree was doing well until last week...the tips started to turn black, i cut them back but it has continued....the tree had nice leaves that turned brownish and then fell off, i was worried but then saw new baby leaves starting to show, but now the black tips have me worried again. the plant is potted in a large container with good drainage. The last two weeks i have deeply watered all my plants 3 times a week as temps have reached and exceeded 100. the plant has always been under a covered patio so not really getting a lot of direct sunlight as to burn it. please please tell me its not a goner lol.