Move to Zone10 .
Even in Zone10, if you shave a tree to the ground every two months ... nothing is gonna ripen ...
More seriously, you can't all of a sudden do it. It takes a good planning to achieve ripening fruits.
The planning will start in October for the following season. You have to take good care of your trees :
1. Overwinter them properly. Don't let them die-back to the ground.
2. Remove all the root-suckers that you have no use for, ASAP. You need 3 to 5 stems in one spot, never more or once more you'll face delayed ripening.
3. Fertilize the trees every month from March to August or September
4. Water them from April to September, depending on the weather, every week to every other way.
5. To start with select known strains that will ripen in your locales... Don't start with Panaché in Zone7 .
6. To start with, plant your tree in a sunny spot. A shady spot will delay both growth and ripening of the fruit.
7. Try to target brebas if you never get a chance to ripen the maincrops - select a strain for that.
8. Good luck !
9. In October, if fruits don't ripen, something is wrong and all you can do is take some towels and cry :) .
PS: Praying for more sun and heat at your place may work too .