The cloud forest is wet most of the year — this is, after all, what makes it a cloud forest. The drier months (June through September) generally offer clearer skies and better visibility for birdwatching, but Mindo can be visited year-round and the birds are present in all seasons.
The rainy season (October through May) means more dramatic clouds and mist, waterfalls in full spate, and the possibility of rain at any time, but also lush growth and the most atmospheric forest conditions. Birdwatching in the mist can actually be rewarding — many species are more active in wet conditions, and the cloud effect in the gorges is striking. Bring waterproof layers regardless of when you go.
Weekends, especially in the dry season, bring Quitenos escaping the city and the town fills up. If you want more space and quieter trails, come midweek. During Carnival (February) and Semana Santa (Holy Week), the town is particularly busy and accommodation should be booked well ahead.