Happy to report that my solitary bees made it safely through winter !
Mason bees (osmia cornuta and osmia rufa) were the first to emerge, followed by tiny resin bees called heriades, pictured below.
You can help solitary bees anywhere, even a balcony with morning sunshine, widlflowers and a bee hotel well protected from the rain are enough. They are not aggressive and do not sting as they have no honey to defend and are such a joy to be around !
More pictures in my Tumblr :-)