According to sources the Saturdays in the Tamil month of Purattasi (mid-September to mid-October) are auspicious to invoke Vishnu in his most supreme form as Venkateshwara for blessings to create wealth. During this month, the Sun is in Virgo, a sign ruled by Mercury. Mercury’s overlord is Vishnu, the Archetype of wealth. Purattasi Saturdays are highly auspicious to participate in Poojas for Lord Vishnu, who can give prosperity blessings on these power days.
Lord Vishnu descended to the Earth plane in the human form of Venkateshwara (Lord Tirupati, the Supreme Lord of Wealth) during the Tamil month of Purattasi. Venkateshwara is the protector of the Kali Yuga and can shower wealth, well-being, prosperity, pleasures and spiritual enlightenment blessings upon those who connect powerfully with him.
Astrologically, each of the four Saturdays in Purattasi is unique and all share the power to reduce the malefic effects of planet Saturn. According to traditional practices, when you invoke Vishnu on these special Saturdays, you can obtain blessings for health, wealth, happiness and career.