When To Prune Apple for Short Tree

I have several apple trees I grafted on Geneva 30 semi-dwarf stock that are approaching seven to eight feet tall, my inteneded height limit so I can work on them without a ladder. I plan to summer prune to keep them at my height target and induce fruiting spurs.

Question: When is best time to do this- any time from now on? I hate to sit by and watch them put out growth that is ten, twelve feet high knowing it will all need to be cut off. Isn’t it better to prune them down to target height sooner rather than later?

Many thanks for ideas.

After 4th of July is what i have been told. But leaving a heavy fruit load on the tops can really limit growth.

Is the idea if you pinch/prune to shape too early in spring/summer fireblight might enter the wound?