Kiwi mature while on the vine but will only ripen after they are harvested. To check if they are mature, cut one in half -- the seeds should be black. To harvest, cut them off with a short section of stem still attached.

I assume this is a rather young vine. If so, things will improve with time. But flavor will still vary from one year to the next according to the sunlight received and prevailing temperatures.

Ok, What’s the purpose of the stem bit? Also what effect exactly does sunlight and temperature have on the flavor?

I’ve lost three new vines already I believe to sunburn and drying, despite being very careful about watering. I guess one would have to put up some sunscreen for the first year at least in these cases?

Kiwi are thirsty plants! They become large vine with large leaves. If you don't have any mulch in their bed, add several inches.

If you twist them off the vine, the often spoil before they ripen.

See this: https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/pnw507.pdf

Thanks Jean. I think I actually read that article couple years ago, but it actually means something now, LOL.