Hi Kavya! Summer is considered the best time to visit Himachal Pradesh starting from March to June. You can participate in various activities such as camping, trekking, paragliding and water sports during this time. The weather is pleasant and soothing. To witness snow and extreme cold, you may consider going in winters too. And Yes you've heard right that in Monsoon generally it's not recommended as few destination also face landslides.
Hi Kavya, the best time to visit Himachal Pradesh is during the summer from March to June. Temperature during these months ranges from 22-37 Celsius. This is the peak tourist season so you may encounter hordes of tourists at popular places. If you want to avoid the crowds then visit in September-October. July and August is monsoon in Himachal and you may face torrential rains and landslides causing delays. It is best to avoid these two months.