Bonalu is a folk festival for Mother Goddess, which is very famous and people love to celebrate this festival during rainy season month of Ashada around July/August and goes on usually for twenty-two days. A minimum of twenty days is conceptually required to fulfil the promises given to mother goddess by carrying out pooja on the very first day and last day.

Bonalu derived from Bhojanalu meaning food, which is offered to mother goddess. Bonalu involves the worship of Mother Goddess in regional forms like Gangalamma, Ellamma/Yellamma, Mutyalamma, Mallanna, Maisamma, Peddhamma, Dokkalamma, Ankalamma, Poleramma, Maremma, Nookalamma and Samakka and Pochamma.

Women carrying Bonalu are believed to possess the spirit of Mother Goddess, and when they go towards the temple, people pour water on their feet to pacify the spirit, who is believed to be aggressive. Every group of devotees offer a Thottelu (a small colorful, paper structure supported by sticks), as a mark of respect to the goddess.

According to mythology, Potharaju the brother of the Mother Goddess. His role is played in the procession by a well-built, bare-bodied man, wearing a small tightly draped red dhoti, bells on his ankles, and anointed with turmeric on his body and vermilion on his forehead. He dances to resounding drums in the procession. Potharaju always dances in front of the Palaharam Bandi, i.e., the procession. He is considered the initiator of the festivities and the protector of the community. He leads the female dancers who are under the spell of the Mother Goddess (known as shigam) to the temple, with lashing whips and emerald neem leaves (margosa) tied around their waists, accompanied by trumpets and drums.

A non-vegetarian family feast follows after the great offering. The meat used to prepare the meal is the meat of a goat or a rooster, that has been ceremonially slaughtered, and later partaken as a meal. Peasants take whatever food they can as a display of affection to the earth goddess and eat it later. Toddy (palm wine) workers also offer toddy which they tap for their livelihood. There is no special scriptural mandate on what has to be offered. As per tradition, offerings are made to the goddess which consists of toddy, along with fowls, sheep and goat. Animals killed for community meals are not considered sacrifices.

Rangam (or Performing the Oracle), is held the next morning of the festival. A woman standing atop of an earthen pot invokes Goddess Mahakali onto her and performs the custom. She foretells the year ahead for the devotees asking about the future. This takes place before the procession is started

The prominent temples in the Secunderabad "Lashkar Bonalu" include Sri Ujjaini Mahakali Devasthanam, Sri Gandimaissamma Temple, Sri Devi Pochamma Temple, Sri Muthyalamma Temple, Sri Peddamma Temple, Sri Dokkalamma Temple, Sri Muthyalamma Temple, and Sri Peenugula Mallanna Temple, among others. Out of these temples, Sri Ujjaini Mahakali Temple, and Sri Devi Pochamma Temple are government temples, government officials and legislators also visit and take part in the festivities.