Well, I wouldn't say "few". Certainly you have to pick and choose.
I eat low carb and eat lots of squash, broccoli, cauliflower, avocado, and have a salad with dinner almost every night. You do have to be careful of dressing to avoid the carbs, but ranch and oil & vinegar work just fine.
And certain fruits are also fine. I eat lots of berries - local strawberries were in season and very delicious. Blueberries are coming into season. Basically, berries are fine. Also, melons like watermelon, cantaloupe, and others. My wife and I often split a small apple.
Nuts are another plant food that works.