The lettuce seed packet showed a mixture of both green and red lettuces. Thus far, all my plants have been green, but now they're getting big enough that at least one plant is changing to its adult colors.
The lettuce is growing slowly. As soon as the first tiny "true leaves" started to appear, that was about when the plants were big enough to sway a bit in the breeze when the fan is on. By now they are actually looking like real lettuce plants. I have a couple photos here, taken a week apart.
The seeds have sprouted!
But the Niwa showed me a surprise before that.