If you’ve ever grabbed a bright orange orange from the grocery store, you probably assumed it naturally grew that way.
Not always.
A lot of oranges are actually green when they’re picked, especially in warmer climates like Florida. The inside can be perfectly ripe and sweet while the outside still looks more like a lime than an orange. Since most shoppers associate orange color with freshness and ripeness, citrus producers often treat oranges after harvest to improve their appearance.
That process has become surprisingly common in the citrus industry, and depending on the method used, it can range from relatively harmless to somewhat controversial.
Why Some Ripe Oranges Stay Green
Orange peels lose their green color when chlorophyll breaks down. Cooler nighttime temperatures help trigger that process naturally.
In tropical or consistently warm climates, that color change often does not happen completely. The fruit can still be fully mature and edible while the peel stays partially green.
This is especially common in:
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Florida
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Parts of Brazil
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Tropical growing regions
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Early season citrus crops
Because consumers tend to avoid green oranges, growers often use post-harvest treatments to make the fruit look more appealing before it reaches stores. (U.S. Food and Drug Administration)
The Main Chemical Used: Ethylene Gas
The most common treatment used on oranges is ethylene gas.
Ethylene is actually a naturally occurring plant hormone that fruits already produce on their own during ripening. Commercial citrus facilities expose harvested oranges to controlled amounts of ethylene in special rooms to speed up the color change process, often called “degreening.” (U.S. Food and Drug Administration)
The process removes the green chlorophyll from the peel so the orange color underneath becomes visible.
This does not usually change the taste much. In many cases, the fruit was already ripe before treatment.
Is Ethylene Harmful?
This is where the conversation gets more nuanced.
Ethylene itself is generally considered low risk in the amounts used for produce treatment. Since it is a natural plant hormone, many scientists and regulators view it differently than synthetic food additives. The FDA allows its use for citrus degreening. (U.S. Food and Drug Administration)
That said, there are still a few concerns worth discussing.
Potential Concerns
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Excessive degreening can shorten shelf life
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Poorly managed treatment conditions may affect fruit quality
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Industrial ethylene is also tied to petrochemical production, which makes some consumers uncomfortable
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Some people simply dislike the idea of cosmetic chemical treatments on food
Research also notes that improper ethylene treatment can contribute to decay or texture issues if the process is not carefully controlled. (Felix Instruments)
Overall though, ethylene gas itself is not widely considered dangerous when used correctly in food processing.
The More Controversial Part: Artificial Dye
Here’s the part many people do not know.
Some oranges are not just exposed to ethylene gas. They are actually dyed.
The FDA has historically allowed the use of a synthetic coloring called Citrus Red No. 2 on the skins of certain oranges. This dye is only permitted on the peel and not the edible inside of the fruit. (U.S. Food and Drug Administration)
The reason is mostly cosmetic. In warm regions, oranges can stay green even when ripe, and grocery stores know shoppers are more likely to buy deep orange fruit.
Why Some People Are Concerned About Citrus Red No. 2
Unlike ethylene, Citrus Red No. 2 has faced more criticism.
Some toxicology reviews and international organizations have raised concerns about potential carcinogenic effects based on animal studies. (Rupa Health)
In 2025, the FDA announced plans to begin revoking authorization for Citrus Red No. 2 as part of a broader effort to phase out certain petroleum-based synthetic dyes. (www.hoganlovells.com)
It is important to note:
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The dye is applied to the peel, not the fruit inside
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Washing and peeling reduce exposure significantly
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Not all oranges are dyed
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Ethylene treatment is much more common than artificial dye use
Still, many consumers are surprised to learn that some oranges may be cosmetically altered at all.
How Common Is Orange Spraying?
Ethylene degreening is extremely common in commercial citrus production.
Industry sources describe it as a “standard” or “common” post-harvest practice, especially for fresh-market citrus sold in grocery stores. (ScienceDirect)
If you buy conventional oranges from a major supermarket, there is a decent chance they were exposed to ethylene during processing.
Artificial dye use appears to be less common than ethylene treatment, but it has historically been used in parts of the United States, particularly:
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Florida
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Some warm southern citrus-growing regions
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Early season oranges that naturally remain greener
Organic oranges cannot be treated with synthetic dyes like Citrus Red No. 2.
Should You Avoid These Oranges?
That depends on your comfort level.
If the oranges were only treated with ethylene gas, most evidence suggests the process is mainly cosmetic and relatively low risk.
If you want to avoid artificial dyes entirely:
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Buy organic citrus
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Look for locally grown oranges
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Do not judge ripeness based only on peel color
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Expect some oranges to naturally have green patches
Ironically, a slightly green orange can sometimes be more natural than the perfectly bright orange ones sitting beside it.
Final Thoughts
The idea that oranges may be sprayed with chemicals sounds alarming at first, but the reality is more layered than most viral posts make it seem.
Ethylene treatment is mostly about appearance and is widely accepted in the produce industry. Artificial dyes like Citrus Red No. 2 are more controversial and are now facing increased regulatory scrutiny.
At the end of the day, this is really a reminder of how much modern food marketing revolves around appearance. Consumers expect oranges to look perfectly orange, so the industry adjusts accordingly.
At P4L$, we believe self improvement starts with awareness. Understanding what goes into the food we eat helps people make more informed decisions without falling into fear-driven misinformation.
Sources
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FDA: Artificial Coloring of Oranges (U.S. Food and Drug Administration)
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Colorado State University Food Source Information on Oranges (Colorado State University CHHS)
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Citrus Industry Magazine on Ethylene Degreening (Citrus Industry Magazine)
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Scientific research on citrus degreening (ScienceDirect)
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FDA announcement regarding synthetic dye phase-outs (U.S. Food and Drug Administration)
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Review of Citrus Red No. 2 toxicology concerns (Rupa Health)
