I think the "seed grown" is just an awkward wording. The phrase, "All fruit trees certified virus free with a FREE FRUIT TREE WARRANTY. Most are UK seeds/grown .... " appears at the beginning of all their fruit tree descriptions and so is not specifically pertaining to the fig in question.
"UK" means United Kingdom, not 'unknown'. so they are saying most of thier stuff is grown in United Kingdom( Britain) and not imported. I am just guessing,assuming, that as an ongoing nursery bussiness they, owners/workers, would know how to propogate figs or other stuff appropriately. but maybe not.... tyty
Grant
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