If you haven’t heard of yarnstorming, we’re here to enlighten you. The website of its perpetrators, Knit the City defines it as “the art of enhancing a public place or object with graffiti knitting.” Also called yarnbombing, the streets of South London were treated to knitted flowers, bees, and beaming suns this spring, continuing into summer. The four girls behind London’s lifted spirits operate secretly, knitting, releasing their creations upon needy street corners.

The reasoning behind it all? Yarnstorming forces people to pay attention to and re-evaluate otherwise forgotten urban spaces. It also turns neighborhoods into art galleries, tells stories, and fosters imagination. And most obviously, it’s a way of making people smile. It’s a colorful celebration of life, art, and London, or whatever city it might invade.

Note: This idea isn’t copyrighted. The girls behind the idea and Knit the City want you to spread some soul, to decorate your neighborhood with knitted daisies, lilies, superheroes, and giant squids. Yarnbombing invaded New York three years ago when artist Agata Olek completely covered the famous Wall Street bull with a bright pink and purple knitted cover. Since then, the city has embraced a twist on the concept (this time actually permitted by the city) with Orly Genger’s current installation of bright nautical rope in Madison Square Park. We can only assume that as yarnbombing gains even more prominence and spreads, artists and knitters around the world will keep innovating and putting their own twists on the idea.

Check out more at Knit the City. Get in touch with the author @LaraElmayan.