Any body who smells the Tulasi leaf which has emanated from Lord Shri Vishnu, whatever sins he has in his body are all destroyed"‪ Shri Vishnu, the Lord of the Three Worlds, takes up abode in the village or the house where Tulasi is grown. In such a house no one suffers calamities like poverty, illness or separations from dear ones.

JAIMINE TULASI PATRAM YASTUR JIGHRATI VAISNAVAH 
TASYA DEHANTARASTHAM HI SARVA PAPAM VINASYATI ~ PADMA PURANA 
"O Great sage, any body who smells the Tulasi leaf which has emanated from Lord Shri Vishnu, whatever sins he has in his body are all destroyed"‪ Shri Vishnu, the Lord of the Three Worlds, takes up abode in the village or the house where Tulasi is grown. In such a house no one suffers calamities like poverty, illness or separations from dear ones.” ~ Padmapurana. 
"Every home with a Tulasi plant is a place of pilgrimage, and no diseases, messengers of Yama, the God of Death, can enter it.” ~ Skandapurana
Om Namo Narayana ~ Om Namo Bhagwate Vasudevaya Namah ~ Jai Shri Vishnu!!