The rainy season we have now in Japan (mid-June ~ mid-July in Kansai) is married with the plums. It’s called the “plum rains”. So these ume are the “rain plums”.
You make think they are not ripe on this photo. It’s true they are very sour and hard. But that’s at this stage of maturation that they are picked and used to make umeboshi (pickled plum).
When they reach this color they are too mature for the salted pickle. When they become soft…they are not sweet, still as sour and less fragrant. Well, mines are yellow and still hard.
Good to make jam !
With kurozato black sugar.
I’ve just put the whole plums, blocks of sugar and water in the home-bakery. Lazy… but I was punished : that splashed and then cleaning the machine was a hell !