"M" wrote

I am a novice gardener and have planted seed potatoes and expect a crop
very soon. I have a lot of foliage which is now flowering but have no
idea when to harvest. I have watered well during the hot weather.

The type of potatoes are Charlotte, Highland Burgundy Red main crop and
Salad Blue second early.

Is there a way of knowing when they are ready?


Charlotte is a First Early so should be ready soon, especially if flowering.
Scrape away a bit of soil and see what you can find.
Salad Blue as a second early will probably take another few weeks or you
could leave it to die back before lifting.
Highland Burgandy Red as a maincrop should be left to die back in the autumn
before lifting and storing.

--
Regards
Bob Hobden
W.of London. UK