I'd pick them now Seasprout, down here it's a major industry and now is harvest time. If you have a glut, put them in a cardboard box somewhere dark/not too warm and they will keep for weeks.

If you use them under ripe for jam or chutney, drop them in a food processor after you've peeled them, only a quick blitz to break the cores down a bit, that has worked well for me and under ripe they keep their colour better when processed.

And go for prepared weights rather than entire, you'd be surprised how much loss there is on a kiwi by the time you've topped and tailed them and taken their fur coats off. Also, if they're on the small side and you make chutney, use 15, works just as well.

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TonyF, Dordogne 24220