If the ground temperature dropped below freezing, what could a farmer growing oranges do to protect his crop?

Answer 1

Oranges don't grow where the ground freezes. If the air drops below 28F, then the ranchers use "wind machines" (large propeller blades on a tall post) to circulate the air. If it will be below 28F for several hours, the ranchers in my area use ground-based sprinklers to coat the fruit with ice to prevent further chilling/freezing.

Answer 2

In most areas where oranges grow, the ground temperature rarely does this. Also, since the trees are fairly hardy, and the crop is on the branches, heating the air around the trees is the major concern.

The traditional solution was "Smudge pots" These are basically large oil burning heaters, which often wind up serving as mail box decorations in former orange growing areas. The smudge pots are filled with oil, and placed throughout the orange grove. Then the farmer burns thousands of gallons of oil to keep the plants warm. Strict air pollution regulations are severely limiting the usage of smudge pots these days, and they have yet, to my knowledge, to come up with a new solution.

Small scale orange growers sometimes cover large portions of their crops with plastic sheeting, to help trap in the sunlight, and what little heat a plant produces.

That's what they DO.

Here's what they could do:

It might be possible to install a huge water heater as part of the irrigation system. As the temperature drops, heated irrigation water would spread out to the plants. This is not an ideal solution, because all the steam would likely condense on the fruit. Technically, this should warm the fruit, but it would probably also get the fruit soaked with water, and if the heating was not sufficient, the orange, and the water around it would then freeze together. Additional watering would lead to additional layers of ice. Also, that much steam coming off an open field would cut down on sunlight, would make seeing around in the orchard harder, and might help spread colds, and other diseases among the workers, who are supposed to pick just before the first freeze.

I guess some fancy electric heater design might be worthwhile. Probably very much so, since it would not interfere with the plastic sheeting much, and the farmers could then use both methods. Go your patent ready?

Answer 3

Anne is right on with her answer. Usually, they only need to protect to harvest, blossoms or whatever for a couple hours until the sun rises. The thin layer of ice will keep them at 32 degrees versus lower.

Cranberry growers do the same sort of thing with flooding their bogs to extend the growing season a few days when necessary. The cranberry bogs are ever built this way for this very purpose.

Answer 4

I can't say for certain about Oranges, but my family (cousins), who grow apples, put out hot air heaters every 15 feet or so under their rows of crops, if a freeze comes before the apples are harvestable. There's a newer option, but it slips my mind right now.

Answer 5

I am not sure if you mean air temperature or ground temperature.
If you mean ground temperature which would be the soil, he could kiss his crop goodbye because the air temperature would be considerably less. If it is the air temperature he could put out smudge pots which generate a dense smoke and hope to keep the frost frost off the trees.

Answer 6

I've heard of farmers in Florida spraying the trees with water so that ice will form on the oranges and keep them at a constant 32 degrees (instead of lower).

Sounds risky, but thought you might want to know...

Answer 7

I looked up protecting orange trees from frost and it listed running sprinklers at the BASE of the trees, or stringing CHRISTMAS LIGHTS in the trees, BUT NOT BOTH THINGS AT ONCE. I am so sorry I gave that first answer a thumbs down. I was sure that answer was just for laughs. How embarrassing!

Answer 8

String xmas tree lights in his trees

Answer 9

hey mindshift.... good for you for your little extra note!

byron1015's answer WAS a good one... and it does work.
cheers