Matsya Purana 57.18

57.18

śrāvaṇādiṣu māseṣu kramādetāni sarvadā.
yasmin‌ māse vratādiḥ syāt tatpuṣpairarcayeddharim.. 57.17 ..

Then he should worship the Moon and Viṣṇu with Kadamba, blue-lotus, Ketaki, jasmine, lotus, sevatî, kuvaja, white kannair and champaka.—16. Hari should be worshiped with all the various kinds of flowers that bloom in various months, from the beginning of the month of Śrâvaṇa.—17.