You could start your own lettuce indoors in a BioDome. I bought one and sowed seeds (flowers) last weekend, and half of the species I sowed are up already today.
website: parkseed.com
search “BioDome”
I got the double one, holds 2 trays of 40 plugs each.
They sell a single one too.
The double BioDome was not much more money than the single.
Very sturdy plastic. I’m very pleased with my BioDome.
It lets me start slow growing seeds indoors now (Wisconsin).
Lettuce is easy to grow from seed.
Park Seed sells that too, naturally. ☺️
I’ve been growing lovely lettuces in dishpan flats (holes drilled in bottoms & on trays) under grow lights in the house all winter for 3 years now. It does so well I keep them going all year so my lettuce never gets bugs & I have more room for other things in my porch pot garden. Lately have done broccoli raab & baby pak choy in those flats, too.