Yuma County, Arizona is known as the Winter Salad Bowl capital.

From lettuce to cilantro to broccoli, the region produces almost all the leafy green

vegetables consumed in the U.S. during winter months.

But farmers there rely on the nearby Colorado River.

And as the West contends with drought and a changing climate, they've had to adapt.

Stephanie Sy has this report.

So I'm going to guess about five days ago.

On a crisp November morning, an introduction on how to grow vegetables in the Sonoran Desert.

So right now, we would be harvesting this crop at peak maturity, probably next week.

Matt McGuire is the chief agricultural officer for J.V. Smith, which grows vegetables on 8,500 acres in Yuma County, Arizona.

I'm standing in a field of lettuce, but I'm surrounded on all sides by desert. How does this make sense? Very fertile soil.

You've got to remember this valley, Yuma Valley, Bard-Wuner-Hadham Valley, they're all formed by the

river. That's the Colorado River, which starts in the Rocky Mountains and once flowed so

abundantly down to this region that it would occasionally flood.

So there's all these sediments from flooding over the years that built up these very rich soils here in this area.

That, plus the consistently mild sunny winters in southern Arizona, have made lettuce growing a cash cow.

You can say, oh, I want to grow them all in Florida.

Well, that's great.

When they don't get hurricanes or excess rains or freeze,

you have vegetables in the wintertime.

There are other places that keep trying,

but they cannot grow consistent quantities and quality of lettuce

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