Reisentraube tomato = yellowing leaves
I know there are tons of previous threads about yellow leaves on tomatoes, but I'm still perplexed. I'm growing a reisentraube tomato in what I think is a reasonably sized container -- an old recycling bin. It's been doing well overall very bushy (I should no doubt be pruning more) and lots of flowers, and in the past couple of weeks it's started setting fruit. But in the past week, more and more leaves have started yellowing, starting from the bottom but now moving up the plant.
They're curling upwards a bit, but not getting brown or crispy, at least so far, and no spots or anything that I've noticed. Just yellow.
Three factors that I can think of: One, we've been getting a fair bit of rain lately. Two, this is the plant that I posted about a couple of months ago, which I accidentally planted in potting soil rather than potting mix -- so it's certainly possible that it's a bit waterlogged from the rain, though I've been trying not to overwater, myself.
The other thing is that this plant (and not the others, for some reason) has a fair number of aphids. I've been trying to spray them off, and have noticed some ladybugs and whatnot, but they're definitely still around. Would that do it?
Again, nothing looks wilted or brown, but the yellowing is of course concerning.