Lettuce you can squeeze in just about anywhere.

Other things? - it completely depends on how much room you have. Peppers can get pretty big. You dont say how big the beds are, or how many peppers you are planting.

Plant things together that have similar nutrient and water needs. Lettuce loves nitrogen, peppers not so much. Lettuce needs lots of water while peppers prefer to dry out some between waterings.

That doesn't mean they can't go in the same bed. They just need to be far enough apart that feeding and watering the lettuce won't affect the peppers much. So that depends on the size of the beds and the number of plants.

Besides nutrient/water needs, comparable size in the plants planted in the same bed help you avoiding overly shading or overly crowding one or the other. So Low-growing plants like lettuce, spinach, cabbage, cauliflower, etc. work well together with the tall plants in other beds.

Dave

It would have helped to say how big, huh? They're about 4x10' each. I'm planning on planting at least 6 pepper plants in one bed. May do a couple of beds because I love peppers.

Too many in one bed of that size?

Peppers are usually 2 sq. feet so in a 4x10 bed, if you stagger them, you can easily get 8-10 plants - if that is all you plant in the bed.

Dave

Super. Thanks digdirt!