It’s in chapter five of his book. (I should mention that he was trying to grow figs as a commercial crop grown in the ground, Justin Brook was already a very successful fruit grower in the UK)
Premise #1:
Many figs grown in the ground in the UK produce ‘long sappy barren growth’ i.e. long internodal growth…..by reducing this internodal growth more figs can be produced in a smaller growing space.
Premise #2:
Fig trees with short internodal growth are hardier.
Aim:
To get the intermodal growth on figs grown in colder climates to be no more than three inches in length in order to maximise fruit quantity without diminishing fruit size.
Method he used:
He experimented on fig trees which were growing more than one stem from the ground, he did not reverse the bark on all the stems (the bark grafts were carried out in April/May when the sap was rising)….the result was the reversed barked stems grew with shorter internodes and therefore produced the desired result of producing more figs in a smaller space.
Justin Brooke uses the example of grafting scions onto rootstocks to achieve dwarfing, as his inspiration to try the above on figs.
Marcel - thank you I'll take a look