Is it to Late for Lettuce Now that it is Warm? Yes and No.

Lettuce is a cool season crop. When it get warm like in the high 80's it prepares to bolt. That is, it turns to flowering and seed production. It's 5/27 and the last 2 days have been nearly 90.

It is probably to late to plants seeds but not transplants. The strategy at this time is to plant in the most shaded area of your garden. Lettuce will grow in pots. Small pots are all you need.You can put transplants into pots and move them to morning sun areas only. This strategy helps prolong the lettuce season.

You could plant seeds if you want to do a cut and snip lettuce garden. Plant them in the most shaded area of the garden. The cut and snip garden is more about taking a few leaves here and there vs. waiting for the full head to form and cut. The lettuce will still produce at baby size when it's warm. You'll get leaves to cut. Lettuce won't typically form a full head when it is warm because it jumps to seed production when the consecutive warm days arrive. When the flower stalk arrives, lettuce usually becomes bitter tasting. So, you snip the young leaves vs. waiting for a big head of lettuce.

Another technique is to create a shade cloth over the lettuce beds. Shade is good at this point in the season for lettuces.