Thanks to the information from the villagers and Alesia through the [Earring of Communication], I found the other 5 field locations easily.
Before going to destroy them, I left the old men 50 Golds each to survive a few days before the Church helped them, and they thanked me to the point of kneeling in front of me.
I thought it was just an exaggeration, but with 50 Gold, they could buy a lot of food from the merchant and survive with their family. Only then did I notice the severe condition of those villages near the border.
But I didn't stay for long and went to the corresponding location of the fields and destroyed them, putting all the flowers inside my inventory.
Because they were spread along the magical border between the two Kingdoms, it was easy to find them. It only took me less than an hour to destroy five fields and kill more than 30 thugs guarding them.