What is this 5 petals blue wildflower? Zone 7
The plant in your photos is an annual wildflower commonly called "borage" or "star flower" of the "forget-me-not" family Boraginaceae. It's scientific name is Borago officinalis. It is an edible plant as well. It originates from the Mediterranean region, but has naturalized elsewhere. Other helpful/descriptive information can be found at the Wikipedia links below.
This is borage (Borago officinalis); it is an herb - the flowers taste sweet since there is a drop of nectar available. Some people say the leaves taste like cucumber but they are awfully hairy.
Edit: sometimes people float the flowers in summer drinks, but to do so is terribly spiffy and superfluous.