Significance
Ashadha Gupt Navratri is the second 'Gupt' (secret) Navratri, falling in the monsoon month of Ashadha. Like the Magha Gupt Navratri, it is observed privately for intense Shakti and Mahavidya sadhana rather than public celebration.
Rituals
The nine days begin with Ghatasthapana and feature fasting, japa and worship of the Goddess. Sadhaks undertake esoteric Mahavidya practices, while ordinary devotees worship the nine forms of Durga through the nine days.
How the dates are fixed
Ashadha Gupt Navratri runs nine consecutive nights from the Pratipada of Ashadha Shukla paksha to Navami; the Ghatasthapana muhurat is set on the first day for your location.