I searched for this in the forums, but can't find the info I'm looking for. I'm pretty new to gardening, my only experience is growing my own hot peppers (pretty easy, and I have a Scoville problem!). Anyway, my fiancé and I decided the pandemic makes it essential that we start growing some of our own food. We started growing Romaine lettuce from the stumps of Romaine we'd bought, and it is going gangbusters. But they look like weeds, rather than the tight bunches we buy at the market. Are we supposed to tie them or something? This seems so basic, I am embarrassed to ask, but can anyone help? Every google search leads to things like studies about washing and chlorine. My fiancé makes the most amazing Cesar salad dressing (so much garlic!), and we would love to have crisp, tight lettuce bunches to make salad. What are we not doing?

I've raised Romaine from seed, and as long as you grow it in cool & moist conditions, I think it will be more like you expect. But I've never 'regrown' it from the core, as you did. In the heat it bolts, (flowers and sets seed) and I wonder if rooting the heart has triggered it to bolt? Lettuce isn't usually good once it bolts. Others may know better. Let your lettuce set seed, then replant that seed in the cool weather?

JHarrisonCowan said: can anyone help? Every google search leads to things like studies about washing and chlorine.

Yes, I can help here!
Add 'edu' to your google search:

'edu lettuce new hampshire'
Or
'edu lettuce'
Or 'edu romaine lettuce'

Your search will return more educational institution sources ( as in harvard.edu) if they exist. I find much more reliable information, such as from agricultural extensions, or university studies, and regional variety recommendations and planting guides.
Welcome, and keep on asking questions, and I'm sure a lettuce expert is on here....

I've seen this method of growing lettuce on Pinterest; I've never done it either because lettuce is so easily grown from seed. What zone are you in? While it's too late in my zone to plant lettuce, I planted mine on March 5 and I'm harvesting now, it may not be too late where you are to still grow from seed. Romaine is one of the best to grow into summer because it is bolt resistant. If you buy seeds look for the words bolt resistant on the package. I've grown Romaine for about 15 years, and I've yet to produce the classic looking one you see in the grocery stores. That particular variety requires more cool spring weather than I have here, but I'm successful growing the smaller and baby Romaines. Two of the three lettuces I'm harvesting now are Romaines, they have the classic shape but are very tender due to picking them at the baby leaf stage. When you harvest also depends on whether you will get those long, crisp leaves. I prefer the baby stage, and that avoids the sudden heat blasts here that causes lettuce to bolt. Lettuce is also excellent growing in pots. Pic below shows romaine three weeks after being planted.

I don't really recommend regrowing lettuce from the bottoms of store-bought lettuce. By the point it's been harvested and put on the shelf at your grocery store, the plant would have already used up most of its energy and won't have enough left to produce leaves as big and brilliant as the first time. Romaine lettuce also takes a bit longer to reach full maturity than most other lettuce varieties, at 75-85 days, so you'd have to wait that long if you wanted a full head of Romaine lettuce. I actually recommend starting several lettuce plants from seed and harvesting their leaves as they grow so that they can continue to produce more leaves while you still have enough leaves for your salad because you're growing multiple plants. Good luck with your salads, they sound delicious!

I grow lettuces under basement lights in narrow trays. Also lettuce and bok choy. You wont get the thick-leaved grocery store product doing that, but you will get leaves. And I prefer celery leaves anyway. So grow the more colorful lettuces as salad add-ins, and the celery and boy choy for the tastier leaves.



And if you cut an individual head about an inch up, it will regrow several times.

Thanks for all the help. I really appreciate it. And as to how the lettuce from stump-grown tastes, I couldn't resist tasting it once it got leaves around 8", and it is actually delicious! I admit I was wary, but so far, it is great. Only dark green stuff so far, not the crispy heart, so Johannes is right--but still I'm impressed. We've got 12 stumps out of 14 thriving.

You indoor lettuce will not be like the grocery store stuff. But you can get leaves. And I grow mine from seeds. The smallest packet will be more than a lifetime of seeds for several people.