Red deadnettle; Ortiga roja

Similar to a nettle in appearance but it is not related and does not sting, hence the name "deadnettle". The leaves have fine hairs, are green at the bottom and shade to purplish at the top.
It is common in terrains altered by man action. They may produced flowers the year, including mild weather in winter. This allows bees to gather its nectar for food when few other nectar sources are available. It is also a prominent source of pollen for bees in spring, when bees need the pollen as protein to build up their nest.