In Jainism, during Chaturmas (chomaasa—the four months of the rainy season), many Jains observe stricter dietary restrictions to minimize himsa (violence against living beings), as this period is when microscopic life is believed to flourish due to increased moisture.

Basil (Tulsi) is generally considered a sattvic and non-harmful plant, and its leaves are sometimes used for medicinal or religious purposes. However, during Chaturmas, some Jains avoid eating leafy vegetables (patra), including basil, because plucking leaves is believed to harm small life forms that thrive during this season.

Practices can vary by tradition and individual observance. Some Jains may refrain from consuming any leafy vegetables, including basil, during Chaturmas, while others might make exceptions for medicinal use. It is always best to follow the guidance of your family tradition or consult with a Jain monk or scholar for personalized advice.