Worshipping God is essentially of three types:
a) Worshipping God as an Absolute Principle b) Worshipping God as an energy form c) A combination of the above two
The first method is indeed difficult. Those who follow the path do not attach much importance of the kind of flowers. Nor do they need to follow any rules of Puja. They can use any flower or offer any fruit.
Because the other two methods involve worshipping the Almighty in the form of some energy, it becomes necessary to use such articles which are conducive to them. For example, Lord Ganapati should be worshipped with tender grass and red flowers. Hence, when we say that particular articles are dear to particular Gods, it only means those articles help us as catalysts.
Any activity or interaction with energy will have its own set of rules and regulations, there can be no total independence. In a chemical laboratory, the person who is conducting tests and experiments will have to follow the rules and principles of chemistry. Similarly, Puja also involves observing certain rules.
However, no such rules apply to worship in which there are no desires and in which the object of worship is the Absolute Principle.
(Bhaktimala May 1998)