Green
All lettuces, including iceberg, grow in the soil.
Lettuces are said to 'bolt' when they grow a central stem which then bears flowers.
it helps the leaf grow
Yes they do However the lettuce you see in the shop have not been allowed to grow to a stage where they were able to do so.
Iceberg lettuce actually doesn't have much nutrition at all...it is mostly water. Greener lettuces, like romane lettuce, are packed with more vitamins and other important nutrients.
Rabbits can eat dark-coloured lettuces (like romaine, green leaf, red leaf, mesclun mix). These sorts of lettuces can be incorporated into the rabbit's daily "salad": too much lettuce, though, can lead to illness (like diarrhea). However, rabbits can't eat white-coloured lettuces (like iceberg, romaine hearts) -- these have little nutritional value for rabbits, and they can lead to illness (like diarrhea). See the related question below for more info about the rabbit diet.
The birds will eat the snails before the snails eat the lettuces
A small shoot that will grow into a leaf or flower is called a bud.
They are difficult to prevent, but you can trap and later kill them by laying rolled up cardboard ( corrugated is good) which they like to congregate in.
Under a leaf.
grow die