Out of my almost 1,000 varieties of apples about 140 are red fleshed of some type, either solid red or red core, red on the outer edge only or red striped through the flesh, pink flesh ones with the same variations and even a few orange flesh ones.
For the most part they are tart, some extremely so, but not all are that way. Some, like Red Devil, Discovery and Geneva are surprisingly sweet.
Not sure how many member of this forum are members of NAFEX but I wrote two articles for the current issue of the Pomona where I talk about red fleshed apples and how there is a large agricultural conglomeration that is developing what they say will be the first good tasting red fleshed apple. Well maybe they will be the first to bring it to mass production but not the first to develop a sweet tasting red fleshed variety, they exist already.
In the United States most of the red fleshed varieties that have been around for a while were developed by Albert Etter in California using Surprise as his red fleshed basis and Dr Nels Hansen in the Dakota's using Niedzweckyana as his basis for red flesh.
For the most part Etter red fleshed apples have green leaves, greenish to yellow skin, green cambium, light pink to darker pink flesh. A few will have more reddish skin.
Hansen developed varieties have reddish leaves, red cambium and darker red flesh.
Part of the fun of being an apple or fruit nut is growing your own seedlings and see what you get. Every year I grow hundreds of seedlings in addition to grafting 300 new trees. Most of my seedlings are trying to get desirable red fleshed varieties. I have one that was a Pink Pearl x Black Gilliflower cross that I named after my wife, it has the yellow skin of Pink Pearl, the shape of Black Gilliflower and light pink sweet flesh. I have one I named after myself, Derek's Pink Dream, that is the same cross but it has the shape and color of Pink Pearl but is sweeter. One that I am going to name this year is one of my favorites after fruiting for the last couple of years, it is a cross between Rubaiyat x Golden Russet and has the outside look of Golden Russet but when you bite into it is bright red flesh.
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