Plants make use of electricity. Some plan cells build up and release electric charges by moving ions like calcium and magnesium around their cells. It is thought that this plays a role in signalling throughout the plant, and some people even suggest that electrical signals could form the basis of plant memories. This long term awareness, dated since the 1880s, has opened up fields of discoveries and scientific experiments in crops growing (electro-culture is understood to help crops growing while avoiding pesticides) and in urban planning (smart cities using plants’ inner electricity to light up city streets and avoid pollution). That plants have memories calls also for a serious cultural re-consideration of the roles and presence of trees in our lives.