Bob Hobden wrote:

Grafted ones flower quickly, it's the ones grown from cuttings that
take years. Ours hardly grew for a number of years and then in the
5th season grew 20ft and a couple of years after that it flowered and
has done so every year thereafter. Trunk is now tree sized.

I can't remember how long this one has been there, many years and last year
was the first time it flowered, very disappointing this year only a few
flowers.