Given the following reasoning and answer, what was the question? This is the relevant information: It is now a week-long festival, celebrated on different days in different parts of India, but usually between 1 July to 7 July.
 The answer: on different days in different parts of India , but usually between 1 July to 7 July
The question Passage: Van Mahotsav festival was started in 1950 by Kulapati Dr. KM Munshi, then the Union Minister for Agriculture and Food to create enthusiasm among masses for forest conservation and planting trees. It is now a week-long festival, celebrated on different days in different parts of India, but usually between 1 July to 7 July. It began after a flourishing tree planting drive which was undertaken in Delhi, in which national leaders participated. The festival was simultaneously celebrated in a number of states in India. Since then, millions of saplings of diverse species have been planted with energetic participation of local people and various agencies like the forest department. Awareness spread as the chipko movement rose in popularity as a crusade to save mother earth..

Question: Based on this passage, when do we celebrate van mahotsav in india?