Bluish greenish tiny balls in my flower pot?

Plant food.

That is "slow release" chemical fertilizer. The balls are encapsulated in something like the gel caps you would find on pills - drugs and vitamins.

However this will all dissolve at once with high humidity / overwatering and release all that fertilizer at once.

I gave up buying plants from Home Depot and other big commercial stores and that is only one reason. Commercially grown plants are artificially "pumped up." They look great in the stores (so people will want to buy them) because they have been force fed fertilizers and grown under intense artificial light - usually with light cycles from 17 hours to full 24 hours a day.

These plants usually fade when people get them into their homes. Then they wonder why, overwater them and dump chemical fertilizers on them (Miracle Gro) and burn the roots. Dead plant.

Another reason why I rarely buy plants (I buy seeds instead) is that the last time I did, it had spider mites, aphids AND flea beetles on it. I don't see well so I didn't spot the bugs in the store. I still have problems with the mites it brought in.

It might be plant food that dissolves in water. My wife has used fertilizer that looks like that.

A type of plant food/fertilizer.