Do you shred the cardboard? (Please excuse dumb question—I don’t have a good theoretical base.)
“Do you shred the cardboard?”
No, I just cut it into pieces that fit around the tomatoes and the cages. It haa helped a lot. Diana in Wisconsin gave me several suggestions for mulch, cardboard was the easiest for me. She also suggested regular fertilizing and using a copper based fungicide. After I took her advise on mulching, fertilizing and using copper spray, I have had barely any fungus in the last two years.
She also told me to never water tomatoes from the top.
Thanks Diana!