We are visiting Shanghai in the middle of April .Is this good time to visit China.

Yes, it is during the best timing to visit the garden. To get there from a hotel on Nanjing Road, I suggest you walk to People's Square metro station to take subway line 1 to South Rail Station, where transfer to line 3 and get off at Shilong Road. Then walk along Dongquan Road to reach. By taxi, it costs CNY50 or around for the whole trip.