Growing vegetables... where??

An excerpt from a book on the climate of Hawai'i:

"Even though summer radiation totals at the high-latitude cities exceed Honolulu's because of longer days, the midday radiation intensity is still higher in Hawai'i. This means that while a person is more likely to get a bad sunburn in summer in Honolulu, bigger vegetables can probably be grown in summer in Reykjavík, Iceland, because of the length of daylight."

Habbla ha. Somebody should have told those taro-farmers in Hawai'i...