Although technically gorilla trekking is available year round, in March, the ground can be wet and slippery, often thick with mud. This means that hikes can take a really long time, be very wet (not good for photography equipment), and quite tough. If you are looking to get an iconic photograph of a mountain gorilla in the rain, then you can make allowances! As a bonus, the gorillas do tend to stick to the lower slopes to stay warmer, and find food more easily.
March can be a good time to see the other wildlife in Rwanda’s national parks, however, as most people who venture to the country are in search a unique experience with the mountain gorillas, this is not the best time to travel to the country as a whole, but it can be done if you so choose..