Ontario in June

May through October gives you the full Ontario experience. Summer (June-August) means festival season, patio weather, and cottage country at its peak. But it also means crowds at Niagara Falls and $300/night hotel rates in Toronto. September and October deliver the goods - fall colors peak in Algonquin Park around October 1st, wine harvest happens in Niagara, and you'll actually get restaurant reservations in Toronto. Temperatures hover around 15-20°C (60-70°F). May brings tulip season in Ottawa and reasonable hotel rates, though weather stays unpredictable. Late spring in Muskoka means black flies, so pack bug spray or wait until July. Winter? Look, it's cold. Really cold. But if you're into it, Ottawa's Rideau Canal becomes the world's longest skating rink, and Toronto's cultural season kicks into high gear with theatre and concerts.