This is the 10432nd most frequent Polish word.
czerwcowego
"Of June" (adjective form).
Describing an event occurring in the month of June, thus the adjective 'czerwcowego' refers to something related to June.
Uroczystość czerwcowego przesilenia odbyła się w parku.
The ceremony of the June solstice took place in the park.
Here, 'czerwcowego' describes the strawberry cake as being associated with June, suggesting strawberry season.
Nie zapomnę smaku czerwcowego truskawkowego ciasta.
I will not forget the taste of the June strawberry cake.
In this case, 'czerwcowego' qualifies the trip as occurring in June.