The Douro is rewarding year-round but has two stand-out seasons. The almond and cherry blossom in March and April turns the lower terraces white and pink. The grape harvest, the vindima, runs from the end of August through September; some quintas still let visitors join the foot-treading in granite lagares, an experience worth timing a trip around.
Summer is hot — temperatures regularly exceed 35 degrees in July and August — and the steep schist terraces hold the heat. Visit early or late in the day if you come in mid-summer. Winter is quiet and damp but the valley is at its greenest, and many quintas are still open by appointment.