Tomato plants, Yes, Its easier to buy plants that are already started, Cukes you can start by seed as well as all types of squash and peppers, Potatoes, You need a lot of room as it takes quite a few plants to make it worth while, It will also matter where you place the garden, If its in full sun, Plants that like full sun will do better then ones that like partial sun or vice versa, But you can plant several types leafy veggies in partial sun, Back of the seed pack will tell you the sun requirements.