Scientific name: Hypericum perforatum
Just as the plant comes into bloom strip the flower stock with your hand, use fresh or dried. Used to treat localized nerve pains, such as sciatica, sprains and cramps, St John's Wort can also be used as an antiseptic and styptic on scrapes, sores and ulcers. The infused oil is used in varicose vein ointments to reduce inflammation, pain and broken veins. St. John’s Wort is considered an invasive weed in many parts of the world. St John’s Wort is best propagated from root divisions made in spring or fall, or by spring cuttings.
This is a photo from the Wikimedia Commons.