Maha Shivaratri is celebrated on the Krishna Paksha Chaturdashi of Hindu calendar month Maagha as per Amavasya-ant month calculation. As per Poornima-ant month calculation, the day is Krishna Paksha Chaturdashi of Hindu calendar month Phalguna which falls in February or March as per the Gregorian calendar.
To celebrate the day Shiva was married to the goddess Parvati.
Process / Procedure
In current form of Puja Vidhi, devotees visit Shiva temples early in the morning. Most people finish Shiva Linga Puja before noon as most temples are closed after that in preparation of evening Darshan. Most Shiva temples open in the evening only for the Darshan and not for the Puja activities. In the morning devotees perform Abhishek with milk and water and offer different items to the Shiva Linga including Bilva leaves, Bilva fruit and Dhatura.
Many people distribute sweet beverage laced with Bhang in the form of Prasad. Bhang, which is made of cannabis plant, is easily accepted in the society as the offering from Lord Shiva.
Most devotees observe full day fast on the diet of fruits and juices. Usually people don't mind to have single fasting meal in the evening. On the next day of Maha Shivaratri, the food which specially includes plain rice and yellow curry made of gram flour is offered to the deity of Lord Shiva and after that it is given to some Baba known as Bham Bole who symbolically represents the Lord Shiva. Only after this offering family members can have the food.
2-3 Hours (Includes time for both preparation for Puja and actual Puja.)