The Bashang Grasslands have four genuinely different seasons. June is canola season, when rapeseed flowers yellow the valleys. July and August are peak summer — green grass, warm days, the Mongolian yurt camps fully operational, and the most crowded period by far. Late August through September is autumn, when the grass turns gold and brown, the birch trees go yellow, and the crowds thin considerably. Winter brings hard cold and snow; most facilities close and the landscape is beautiful but inhospitable.
For horse riding and yurt camping, July through September is the window. For photography and solitude, late August and September are the best combination. The canola in June is worth seeing but the crowds and logistical pressure around peak bloom (usually mid-June) can be intense.