Q.Grapes Not Growing
I planted Purple grapes and green grapes 16′ apart on trellis same soil same water same nutrients purple grapes still growing 2 or more inches per day green grapes hit 7 feet and have not grown even 1″ in 2 months I do not know why Both were planted this Spring Purple grapes are even producing side shoots and the main trunk is still growing more than 2″ A-day green grapes the leaves aren’t even getting bigger it’s completely stalled

Certified GKH Gardening Expert
You don't mention what kind of grapes that you have planted, but it seems that they have different environmental needs. One of them may be more sensitive to hot weather than the other.
Be sure to care for them, properly, for the best growth. These articles will help: