Circles play a large part in Polish mythology. Most Slavic people worshipped in natural circles and groves; and it plays a large part in all kinds of magic. In all traditions, circles can be made of with lighted candles, drawing circles in the soil, or with natural objects and tools. They are used to surround evil or protect oneself from it.
The first definitive reference to the Slavs and their mythology in written history was made by the 6th century Byzantine historian Procopius, whose Bellum Gothicum described the beliefs of a certain Southern Slavic tribe who crossed the Danube river heading south in just two days.
This is contrary to the usual concept in Indo-European mythologies, in which the Sun is usually associated with male deities and Moon with female ones, but identical to the picture in Baltic mythology, which is most closely related to Slavic.
Krasicki, Ignacy (tr by Gerard Kapolka) Polish Fables : Bilingual.
In all traditions, circles can be made of with lighted candles, drawing circles in the soil, or with natural objects and tools.
A circle must be drawn around it in order to harvest it, and the seeker had to deal with demons trying to trick him/her into distracting them from their goal.
Spoiling may be averted by lighting a candle if you not face to face with the culprit, or spitting on the ground, and by throwing dirt in the direction of the culprit walking away.