CC Ādi 13.70
kṛṣṇa-pūjā kare tulasī-gaṅgājala diyā
With this consideration, Advaita Ācārya Prabhu, promising to cause Lord Kṛṣṇa to descend, began to worship the Supreme Personality of Godhead, Kṛṣṇa, with tulasī leaves and water of the Ganges.
Tulasī leaves and Ganges water, with, if possible, a little pulp of sandalwood, is sufficient paraphernalia to worship the Supreme Personality of Godhead. The Lord says in the Bhagavad-gītā (9.26):
tad ahaṁ bhakty-upahṛtam aśnāmi prayatātmanaḥ
“If one offers Me with love and devotion a leaf, a flower, a fruit or water, I will accept it.” Following this principle, Advaita Prabhu pleased the Supreme Personality of Godhead with tulasī leaves and water of the Ganges.