The 15th of Av is the Jewish day of LOVE

& people enjoyed the harvest of their vineyards , by one account.

The Meaning of Tu B' Av :

http://www.aish.com/jl/hol/o/48955491.html

Often , it is considered the time to get married.

Blessings,Lynnette

Also: 

On 15^th of Av, people enjoyed the harvest of their vineyards. And this fun festival has given the Jewish people …" from:

https://www.yardenit.com/jewish-holidays/tu-bav-festival/