If you can, that wouldn't
If you can, that wouldn't hurt. You can also use straw (it works if the plant's root system is in soil) with a bit of dirt on top. Remember, the object is no sunlight. Or, you can just stay put and have a bit smaller harvest. Your key next season is to start about a foot below the box with your initial layer of compost and the seed potatoes. You'll be fine as you have described your situation though.