Bhadra Yoga is one of the pancha mahapurusha yogas reckoned in the very important planetary combinations in predictive astrology. Bhadra yoga is constituted when the planet Buddha (mercury) occupies a Kendra (quadrant house) from the ascendant (first house) in the natal chart, which must be in its own mulatrikona or exalted sign.
Since Mercury owns Gemini (Mithuna) and Virgo (Kanya) signs and gets mulatrikona strength and exaltation in Kanya Rashi, the presence of this planet in a Kendra house (first, fourth, seventh, tenth) in the natal chart from the lagna (first house) in these two sings constitutes the celebrated bhadra yoga.
According to some texts, the yoga will be more effective if Mercury happens to be in Virgo since that is its mulatrikona and exaltation sign too, apart from being its own sign.
Ownership, mulatrikona, and occupation of exaltation signs indicate the potency of the planet in ascending order.
According to some other classical texts, even if Budha is found to be in Kanya or Mithuna Rashi, and in a Kendra house from the moon sign in the natal chart, this yoga gets constituted.
Budha is believed to be the ruler of the mental faculties in Hindu astrology, which make the native quite worldly. It teaches the person how to cash in on his talent. The presence of bhadra yoga accentuates these attributes in the native.
A classical text says that a person having bhadra yoga will be eloquent, an expert in understanding shastras, and debating over them. The person will be devoted to people with knowledge of Brahman and devatas, will be somewhat of a dark complexion, proficient in arts, busy with his own work and long lived. The person may suffer from excess vata, pitta and kapha doshas.