Ann Redloff of Vredendal writes We were hit hard with very little seasonal rain for about 2–3 years. We only watered when allowed, concentrating on the citrus and avocado trees in our garden. The avo tree bears huge fruits which, when cut open, are edible but this year they had lots of dark marks on the outside. What could be causing this?
JJ replies The most common problem in avocados is anthracnose, a black blotch fungal disease. Unfortunately, this can affect the fruit as well as the leaves. The dark spots on the flesh of your avos looks like anthracnose, but the outside looks like fruit fly damage. The only way to treat anthracnose is to use either Mycogard or Odeon. A good fruit fly insecticide is Spray-Kill 5.