According to the folk calendar - Akulina Grechishnitsa

Akulina Buckwheat is celebrated according to the folk calendar on June 26 (June 13, old style). The name of the date was partially borrowed from the church day of honoring the memory of the holy martyr Aquilina of Byblos. Aquilina lived in Phenicia in the town of Byblos in the 3rd century and was a righteous Christian. At the age of twelve, the girl persuaded her peers to accept the faith of Christ. For this, she was reported to the local ruler, who ordered the girl to be tortured. They beat her, forcing her to renounce her faith, then burned her head with a hot iron. The deceased Aquilina was thrown outside the city, where an angel of God appeared and resurrected the martyr. Then the girl appeared to the ruler, declaring the power of the Lord. Frightened, he ordered Akilina's head to be cut off. On the way to execution, the Lord took the soul of the child to himself, and the cat was forced to execute the dead body of the saint. Akulina was popularly nicknamed the Buckwheat Girl, as the peasants celebrated the festival of buckwheat. On this day they tried not to work in the field, believing that the land would not produce buckwheat. But the sowing of buckwheat was planned 7 days before Akulina Day or 7 days after the date. In the morning they prayed to Saint Aquilina for a rich buckwheat harvest. The owners cooked buckwheat porridge and boasted about it among themselves, then treated it to hungry passers-by, and they thanked the owners and wished that the buckwheat would produce a lot. Another name for Akulina’s day was “Put up your tails.” During this period, it became very hot outside, and annoying insects appeared near the livestock. Flies, gadflies, midges and midges circled around the cows, stinging them painfully. From them, the cattle became restless: they often swung their tails, ran through the meadows, ate less, as a result of which their milk yield decreased. In addition, insects were carriers of diseases. On Akulinin's day, caring owners tried to protect their livestock and alleviate their suffering. To do this, the cattle were grazed at sunrise, taken to the river during the day, and then locked in cool barns. To repel insects, cows were sprayed with tincture of wormwood, mint or laurel. Even peasants suffered from insect bites - mosquitoes flocked to them. Due to the fact that during Akulina Buckwheat the cattle nervously rushed about the fields, their milk was considered unfit for consumption. Usually buckwheat porridge was cooked in milk, but on this day they refused it. This belief came from the belief that Akulina’s milk became harmful and reduced her health. If you noticed an abundance of midges on Akulina Buckwheat, you prepared for fine days. Watching the free flight of bees from the hives, the residents expected a clear day. The arrival of a large gadfly foreshadowed a generous grain harvest. If the dog rolled out in the grass, then the weather was expected to worsen.