Look what I’ve got

We've had Casablanca growing in 10 L polypots (1 seed potato) and 20 L plastic pots (2 seed potatoes). The polypots were harder to keep moist during the very dry May. Initially I was disappointed with the yield, but now they've had longer to bulk up we're getting 1.6 kg from a 20 L pot, which isn't too far off my target of 1 kg per 10 litres of growing medium. They were grown in a mixture of old tomato/pepper potting mix, coffee grounds and very rough, very unfinished hot compost.

Ants in the bags sounds like the growing medium got too dry.