The phrase money doesn't grow on trees means you must not spend too much money as there is only a limited amount of it.
My daughter Claire wants a car for her 17th birthday, but I can't afford it. Money doesn't grow on trees!
"Mum, can you give me some more pocket money?"
"No I can't – money doesn't grow on trees, you know."
The phrase money is no object means that you have a lot of money available to spend.
He lives in a mansion, has three sports cars and goes on holiday every month. Money is no object for him.
You can often see Buddhist 'money trees' in Thailand. The tree shown above was part of a ceremony to mark Vesak Day, the annual celebration of Buddha's birth, enlightenment and death.