Mbh 13.98.5a

"'"'Sukra said, "Penance first sprang into life. Afterwards came Dharma (or compassion and other virtues). In the interval between started into life many creepers and herbs.[439] Innumerable were the species of those. All of them have (the deity) Soma for their lord. Some of these creepers and herbs came to be regarded as Amrita and some came to be regarded as Poison. Others that were neither this nor that formed one class. That is Amrita which gives immediate gratification and joy to the mind. That is Poison which tortures the mind exceedingly by its odour. Know again that Amrita is highly auspicious and that Poison is highly inauspicious. All the (deciduous) herbs are Amrita. Poison is born of the energy of fire. Flowers gladden the mind and confer prosperity. Hence, men of righteous deeds bestowed the name Sumanas on them. That man who in a state of purity offers flowers into the deities finds that the deities become gratified with him, and as the consequence of such gratification bestow prosperity upon him. O ruler of the Daityas, those deities unto whom worshippers offer flowers, O lord, uttering their names the while, become gratified with the offers in consequence of their devotion. The (deciduous) herbs are of diverse kinds and possess diverse kinds of energy. They should be classed as fierce, mild, and powerful. Listen to me as I tell thee which trees are useful for purposes of sacrifice and which are not so. Hear also what garlands are acceptable to Asuras, and what are beneficial when offered to the deities. I shall also set forth in their due order what garlands are agreeable to the Rakshasas, what to the Uragas, what to the Yakshas, what to human beings, and what to the Pitris, in proper order. Flowers are of diverse kinds.