rind

Tree. Taken Sept. 2012

I'm not as familiar with Ruby Red (I have Rio Red), but I think you still have a month or two to go, for the beginning of peak ripeness here in California. My Rio Red grapefruits are not coming into ripeness until February through June. And no, you cannot always rely on citrus skin coloring up. For the most part here in S. California, the skil will get fully colored by the time the fruit is ripe. But, if we have prolonged warm nights, you can still have a little green on the skin. Not so prominent with later citrus (like grapefruit), as they ripen when we tend to get our colder evenings, which helps to color up the skin. Patience, Grasshopper. You still have at least a couple of months to go to peak ripeness.

Patty S.

Here is a link that might be useful: UC Riverside Citry Variety Collection: Rio Red Grapefruit