Modifiers matching lettuce:

• hearty,
• new,
• bitter,
• small,
• crisp,
• mixed,
• dark,
• leafy,
• fresh,
• torn,
• mild,
• clean,

Simple categories matching crisp:

• apple,
• leaf,
• vegetable,
• material,
• wine,
• green,
• food,
• veg,
• ingredient,
• lettuce,
• item,
• fruit,
• veggie,