Hello.How to speed up to ripe a nectarines? Thank you.

Peaches and other stone fruit will not actually ripen after picking, which is why that out-of-season peach from Peru doesn't have that oh-so-luscious taste of a peach picked from your backyard tree in June, even though it may be soft. The apple-and-paper bag hint will SOFTEN the peach, but it will not get any sweeter.

Put it in a paper bag with an apple. The apple will release ethylene gas which will make the nectarine ripen more quickly.