3 weeks in, I figured it was time to thin the tomatoes. Since I had planted two seeds in each square, some had multiple growing tomatoes. For each square that had two, I gave the smaller, weaker tomato the chop. I now have exactly two tomato plants for each variety.
The Yellow Canary had one square that had no plants and one square that had two plants so I carefully separated them out into two new squares. This definitely counts as different treatment, so I’ll record these results with an asterisk, but I was more interested in learning as much as I could even if the experiment wasn’t perfectly controlled.