It was a Echium Pininana! I've just googled it and it looks exactly the same. Thanks so much everyone for all of your suggestions.
Unfortunately I was just wandering randomly so didn't get a picture. I don't think it is a hollyhock or a clome. It literally is just one huge...
I saw a plant which I am desperate to identify while walking past somebody's garden the other day. It was tall (around 7 or 8 ft) and thin,...
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