As far as I am concerned this relates to good unfortunately "Old fashioned" Manners. if it is not yours then ask it doesn't take much and you would probably find you would be given what you ask for. Politeness and honesty count in my view. Hunkering down waiting for replies
But the question was ‘Who owns the plants’ and the answer is still the garden owner owns the plants !
My partner regularly brings home pruning from clients' gardens, and also plants that have been thinned out or even completely pulled up due to not being wanted. They sit down the side of our house until she finds a home for them - often in other clients' gardens! She looks on this as a form of rescue/ recycling, while her clients see it as keeping something out of their green bins.So yes, this is common practice, but I can understand that you might be narked if this gardener is doing it surreptitiously, particularly if he is removing large plants that you wanted to keep.Overall though, I'd like to ask: are you happy with them as a gardener, and could you honestly say you pay them what they are worth? My partner has clients that involve a 20 mile round trip and an hour of unpaid travel; she works come rain or shine and has to supply her own work clothing and tools. I keep telling her that her business model is crap, but she doesn't want to complicate things at this stage of her life 🙄I'm not gonna say "wind yer neck in" cos it's your garden and your choice, but if it was me I'd have to put it down to "perks of the trade"