Hope you get a bigger harvest next year. I grow potatos too. My experience with the red Icelandic ones is that they are smaller and grow slower then for example "Premium" or the yellow bigger once I get in Iceland called "Helga". Maybe it´s the same with your red once? I´m experimenting with two different types as well now from Holland. Looking forward to harvest but I wont be doing that here until end of August or beginning of September. Then the leftover potatos from the house grow from the compost heap we have in the garden and I always get potato grasses coming up from the salad bed as I put compost on the vegetable beds. So much fun growing potatos and trying different methods :D