Our area produces 90 percent of winter vegetables for the entire country; harvesters say the effects of freezing temperatures could spread beyond the crops to have a widespread negative economic effect.

"Prices have basically doubled. This time last year we were shipping cartons of lettuce, 24 heads in a carton, for $8, $9. And right now, it's more than doubled to $20 to $25," said Vic Smith, president of JV Smith Companies.

Local farmers said this price hike is due to a decrease in supply. When there is a freeze warning, crews come in to work later, with limited hours to try to meet the demand.

"Unfortunately, means we're going to harvest later. And in times like this when it gets dark at 5:30 [p.m.], we may not be able to get our orders because of the cutting times we have to harvest the orders that we have," said Sonny Rodriguez, president of The Growers Company.

Another factor affecting market prices is the quality of the product, which can be damaged by the freeze.

"First of all you got dehydration of the lettuce; you don't have the weight conditions so you can't harvest all the lettuce. Plus you have epidermal peel. The top cap of the lettuce gets problems, so we actually have to clean the lettuce, so it slows down harvesting," Rodriguez explained.

Local farmers expect the supply to be tight for at least the next two to three weeks, causing a bump in wholesale prices.

On a retail consumer level, farmers say they cannot control the price--that is up to the store selling the lettuce.

"A lot of stores book at contract levels, so they may not have to adjust their prices significantly," Smith said.

Farmers and harvesters said the price increase for wholesalers should be temporary, with the lettuce supply expected to increase after a few weeks when temperatures are no longer a problem.