This is my first year growing tomatoes so I honestly had no idea what I was doing. We had some old wire fencing that I bent into cages and they seem to be doing really well. I have two determinate and an indeterminate. I decided to go with Roma VF, Indigo Rose, and Black Sea Man. Does anyone have tips in preventing cross-pollination? I'd heard that using muslin bags around the flowers works to preserve heirloom purity but I want other ideas.