GoodGilligan
Lettuce plants are a cool weather crop, and even though it isn't the goal, lettuce plants flower and produce
seeds. The weather/environment plays a big part in when the lettuce plants begin flowering. That's what is refers to as "bolting." Instead of being a nice round head of lettuce, when they bolt (begin to flower) they begin to grow tall (tripling in height, and even more). Basically when the weather gets too hot, the lettuce plants know they will die soon (in nature), so they begin to flower and produce seeds to reproduce.
You can either harvest the lettuce heads as the whole plant (like they sell in stores), or you can just pluck leaves off the plant to eat as it grows throughout the plants whole life. But if you want to know how many heads you'll need to harvest weekly to feed your family, you really need to figure out how much your family eats to have a starting point (you know your family's habits better than anyone else would). Not everybody's eats the same size salad, especially kids that tend to eat much less than adults do. I eat large salad myself, in fact I use a glass mixing bowl as a salad bowl (7 inches wide, and 3.5 inches tall), and stick all the goodies in my salad I can find in the fringe.
I even often make my own croutons from old bread I cut to crouton size, then let dry out on low in the toaster oven. Then I'll saute them lightly in butter (or margarine) and add seasonings to them (perhaps I might even add a spirits of olive oil as well). A salad dosen't get much better than that. Heck you can make a large zip-lock bag full of croutons yourself for the price of a cheep loaf of bread, or practically free from bread that would otherwise wind up in the trash because it's old. We always seem to have partial loves of left over french bread piling up in the freezer (taking up all the space).
Also each variety of lettuce will have their own growth rate and size, and the actual environmental conditions will affect your growth rate, so it's hard to say how many plants you'll want to be growing for a continuous supply without an idea of the quantity that will be harvested, as well as the seed to harvest for the varieties you want to grow.
P.S. fintuckyfarms
I wrote this post before I read the quoted section in your post/reply. So I didn't realize there were reply's in that section. To separate what you want to quote you can just highlight the part you want to quote, then click the quote icon (4'th from the right on the bottom row). That way you can easily separate the quotes from the reply's and it makes it easy to tell which is which like this:
the reply's.
the reply's.
the reply's.