tomatoes had black streaks on top; looked like bugs but no. What is it how to prevent?

Answer 1

I can´t picture what you mean but I´ll say could be the honeydew from aphids or white fly with fungus or it could fungus if they have cracks. If you have the first damage try to control the pest with water and soap and if you have the second damage try water your plant correctly to prevent fruit cracking and won´t the damage tomatoes when you pick them just slice off the damage

Answer 2

add lime to area you are planting tomatoes in. A heaping tablespoon of epsom salts in each plant hole (deep enough not to touch roots) will also help this problem.

Answer 3

i would answer your question could i understand it.