Potato flowers

A flower has appeared on the potatoes so it must be nearly time to harvest them. I’m not sure if I need to wait for lots of flowers or just the first ones - any ideas? They’re first early potatoes.

This evening I met up with three others in a friend’s garden to celebrate a 60th birthday. It was a low key affair but nice to meet up in person and have a meal together. The rain came at 8 as forecast but the large garden parasol over the table kept us fairly dry.