Copper sulphate, or bluestone, is an effective fungicide that also kills many plants including harmful algae, prohibits effective root growth, and has powerful anti-microbial qualities. The use of bluestone to protect potato crops from potato blight (a major contributor to the Irish Famine) is now discouraged, as it leads to excessive copper residue in the soil.
Those living in stone cottages like this soon learned that south facing walls grew warm in the heat of the sun and were great places to grow a few flowers. Cracked iron pots made great planters, and the fruit or flowers grown would add a touch of luxury to an otherwise spartan existence.
The traditional half-door allowed daylight and fresh air into the house whilst keeping hungry livestock out and crawling babies in. It also served as a comfortable leaning post for the inhabitants as they looked out on the day.