This was a disaster. It was the old problem with tone. I need to pre-mix the colours because it’s hard to get the tones right when mixing on paper, one colour over another. I think I got the difference in colour between the two tomatoes quite well (one was more yellow than the other), but I used a brush that was too big a sploshed all over the place on the stems.
I had to go over an over the paint to establish the tones, which I didn’t get right the first time.