The average first frost date in our area is November 15. In early November you can still seed mustard greens and radishes. If you are looking for lettuce, peas or spinach you can be successful by putting in transplants.
The slower growing cole crops that you put in your garden back in August and September are bursting into their glory right now. Your Brussel sprouts, cabbage, cauliflower and broccoli grow best at a monthly mean temperature of 60 to 70 degrees F. This occurs when temperatures are 80 degrees F. or less during the day and 60 degrees F. or less during the night. In our part of Texas that is right now.
One special plant that you could plant in your garden now is strawberries. Strawberries are cold tolerant and should grow through the winter without covering to protect from the cold. You may need to protect the plants and fruit from slugs and snails with slug and snail bait. If you select the correct varieties for our growing area (consult your local nursery) you will enjoy a hard strawberry harvest in next spring. For best results you should remove all runners, blooms, and small fruit from the plants until January. This special pruning allows the plants to concentrate on developing roots and foliage to maximize the spring crop.
Of course November is also a good time to plant herbs. Cilantro, Dill, Fennel, Parsley and all perennial herbs such as Chives and Oregano can be planted now.