Hi!
I do grow the "Marvel of Four Seasons" lettuce, and found that while it doesn't go bitter or bolt as fast as some - it is still best done in the other seasons! Last year, i began growing a lettuce that holds longer into the warm times. It's called 'Jericho', and is a romaine type. Someone told me it was developed around Israel to be more heat tolerant. Once, i made a shadecloth frame over one of my lettuce beds, and compared that to the one next to it w/o. It made a good difference! You might like to try that, if a week or two of tastier lettuce appeals.

Thanks gladgrowing I will try your suggestions.
Meanwhile the lettuce will not be wasted, I will make 'Soup a la Crecy' from them. This is a most delicious soup from my Mrs. Beaton Recipe book. You can use lettuce that has gone to seed as the cooking destroys the bitter taste. I also use the rough outer leaves of iceberg lettuces.

Thanks for the hint, too! I had to look up the recipe, as i have never had use for more than a little bitter lettuce.
Is this the one??

Soup a la Crecy
2.25lt (4 pints) Medium Stock
600ml (1 pint) Lentils
115ml (4floz) Rice
4 Carrots
2 Onions, sliced
2 French Rolls, crumbs only
1 Cut Lettuce and Chervil
50g (2oz) Butter

Put the vegetables with the butter in the saucepan and simmer 5 minutes.
Add the lentils and 600ml (1 pint) of the stock and stew gently for 30 minutes.
Add the remaining stock.
Allow to boil for another hour and add the crumb of the rolls.
When well soaked, rub through a tammy.
Have the boiled rice ready.
Pour the soup over and serve.

Time: 1¾ hour.
Average cost,1s. 2d. per quart.
Sufficient for 8 persons.
Seasonable all the year.

SOUP A LA CRECY

126. INGREDIENTS - 4 carrots, 2 sliced onions, 1 cut lettuce, and chervil; 2 oz. butter, 1 pint of lentils, the crumbs of 2 French rolls, half a teacupful of rice, 2 quarts of medium stock No. 105.

Mode - Put the vegetables with the butter in the stewpan, and let them simmer 5 minutes; then add the lentils and 1 pint of the stock, and stew gently for half an hour. Now fill it up with the remainder of the stock, let it boil another hour, and put in the crumb of the rolls. When well soaked, rub all through a tammy. Have ready the rice boiled; pour the soup over this, and serve.

That's the one!. My recipe has 1.75 litres chicken stock and 100 gram red lentils. Also I puree the soup in a blender and cook 100 g - 1/2 cup rice and add this to the soup. The rice turns it into a substantial meal and is optional.