My Autumn / Winter salads this year consist mainly of endives and radicchio, with just a few lettuce. Here we see endives at the top of the photo and at the left, with young radicchio at the bottom and lettuce in the middle.
Many types of radicchio / chicory are very hardy and will survive even extremely low temperatures. The Grumolo varieties (available in both red and green) are very good in this respect. Endives are not so hardy. They will tolerate a light frost, but not prolonged sub-zero temperatures. When it gets really cold I usually protect some with individual bell-cloches. Likewise, if you choose wisely you can grow lettuce even in mid-Winter (try "Winter Density" or "Valdor"), though without protection it will normally just survive, and not grow bigger until the Spring.
My salads bed is covered with netting to deter the "diggers" (foxes, badgers and cats).
Without netting, the plants would inevitably be decimated. I think the foxes / badgers furtle around looking for worms near the roots of the plants, rather than deliberately digging up the plants. Perhaps this is the penalty for having rich soil with lots of worms in it? In that photo above the big plants in the foreground with rounded leaves are radicchio. The leaves are green at present, but as the weather gets colder they will turn darker and the inner ones will become red.
Over on the garden table I have three pots of lettuce seedlings - ones that were surplus to requirements and never got planted.
I have recently realised that these are a good source of "Baby Leaf Salad", so instead of being thrown away they are being cropped while I wait for bigger lettuces to mature.
Amazingly, the slugs don't seem to have found them up there on the table.
Although I am not growing any at present (Jane doesn't like them), Oriental Brassicas are another good cold weather crop, especially if you can provide protection - and it's not too late to sow some seed if you can. This photo shows Mizuna, whose deeply-serrated leaves provide visual impact to a salad as well as a mild pepperiness. Red Mustard, Mibuna, Komatsuna and "Green in Snow" Mustard Greens are also worth a go.
I would like to show you some photos of Winter Radishes too, because I know that these are supposed to be good for growing at this time of year. However, I have tried them two years in a row without success. Both times they produced lots of leaves and woody stem growth, but no useable root. Have any readers had better luck with this crop?