In a perfect tomato world, with the perfect conditions, there would be no pests, no disease, tomato vines would stand straight no matter how heavy, and abundant warm weather for tomato plants to flourish. Unfortunately, it isn’t a perfect world. There are bugs, birds, raccoons, all sorts of diseases, vines fall over because they are too heavy, and there isn’t always optimal temperature and humidity.
The San Marzano tomato plants have been hit hard with aphids and now, grey mold, which is caused by a fungus called Botrytis cinerea. Apparently grey mold loves humidity and it is always humidity in my area. My tomato plants last year had grey mold, but I thought if I gave the plants more spacing, it wouldn’t be too much of an issue. The only plants that do not show signs of grey mold are the yellow sun sugar tomato plants. The husky cherry red and early girl has some minor spots. I am trying to prune off as much of the grey mold as possible on those two and hopefully I can control it that way.
Grey Mold 
Grey Mold
For the San Marzano tomato plants, I’ve had to throw away more inedible fruit than harvest so it is a sign to me that I have failed to keep grey mold under control. I will probably end the season early for these plants as it is no longer worth the effort. I am a bit disappointed, but challenges are expected when I am still learning about growing fruits and vegetables.
My Small Space Gardening 