We've moved from 2.5 acres of owned property to a rental house with tiny "professionally landscaped" yard that I am not allowed to dig up for a garden. This article prompted me to consider scratching up the bits of weeds out of the flower beds and throwing last year's lettuce seeds into those beds. How's the landlord gonna know I'm growing veggies back there?
Anyway, I'm trying an experiment with leaf lettuce heads (bought from the grocery store for now). I get them home, spray them down in the sink to wash them, then stick the whole head into one of those African violet-type pots (the kind with the base you put water in and the insert for the plant that absorbs water as needed). I put just enough water in the insert to cover the root part (which, of course, has been cut). I've had success with the lettuce keeping at least three or four days this way, out of the refrigerator, and it's out there looking inviting to eat so we do think to eat it.
Really, it actually looks like a pretty little houseplant...
I'd be willing to wager that, as heads of lettuce grown outside get big enough to pull up, you could bring a head or two inside and start more seeds in their place. I might do this with Black Seeded Simpson and leave the more exotic lettuces outside to cut and come again.
What a cool idea, Diane - lettuce as an edible houseplant! Some of the red leaf lettuces are especially gorgeous; it seems a shame to not appreciate their beauty for awhile before eating. And I bet you're right about bringing heads in and starting new seeds in their place - just be sure to amend the soil with some compost to replace the nutrients the first heads used up.
Lettuce grows pretty fast, so you're sure to have a continual crop if you stagger the plantings and have a few going at the same time.