Thanks everybody, for good information. Sorry for the slow replies from my side.

We have arrived in London yesterday. The weather is grey and there are autumn leaves in abundance. Lovely.

Thursdayd: the sore foot is such a hassle. The trick seems to be to stop walking before it is really painful. This makes for more stops for coffee and people watching.

Thanks again to all of you. If the weather and my foot cooperate, I should go to the gardens by Wednesday of next week.