Centaurea cyanus

Cornflower - Flowering from May to October, the Cornflower is not a native plant. Often seen in wild flower beds. Its name comes from growing wild in crop fields as weed crop in the past. It also has white, pink and maroon flowers. The most common though is the lovely blue we see here. This one popped up in my garden at Greaghnafarna Co. Leitrim.