Why is tulasī not offered to Gaṇeśa?

a Purāṇic story makes tulasī unsuitable for Gaṇeśa’s regular pūjā; offer dūrvā, red flowers or śamī leaves instead.

Tulasī is so sacred that many people assume it suits every deity. But tradition keeps it for Viṣṇu and his forms, while Gaṇeśa’s own favourites are dūrvā grass, śamī leaves, red flowers such as hibiscus, and modaks. Just as each guest has their own taste, each deity has offerings that are considered especially dear.

Many families make one exception: on Gaṇeśa Caturthī some offer a tulasī leaf among the twenty-one patrīs (sacred leaves) used that day. Follow your family or regional custom on this.

If a tulasī leaf has been offered by mistake, there is nothing to worry about. Simply offer dūrvā with a short prayer and carry on. Intention matters more than any rule of offering.

Tradition says a young woman named Tulasī wished to marry Gaṇeśa while he was in meditation. When he declined, words of displeasure passed between them, and since then tulasī is kept away from his regular worship.

Source: Brahmavaivarta Purāṇa tradition · Offer instead: dūrvā, śamī, red flowers

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