Make Your Horse Invisible to Flies — With Plant Oils
How Renoura works on a different level than the chemical sprays everyone else is using — by using natural plant oils to do something they can't.
By Wendy Holloway · Updated May 2026
If you've tried three fly sprays this summer and your horse is still covered in welts, it isn't you. It's that every one of those sprays is built to do the same thing — and it's the wrong thing. Here's how Renoura works differently.
The synthetic chemistry every major fly spray brand is built on has been losing potency since the 1980s, and the manufacturers have spent the last forty years compensating with price hikes and additive boosters instead of reformulating. There's a different category of fly spray now — one that doesn't try to kill the insect, but instead makes your horse impossible for her to find. Here's why it's the smarter long-term choice.
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1. Every chemical fly spray is built to kill the fly. Renoura is built to hide your horse.
Conventional sprays are insecticides — they try to kill or repel the fly after it's already landed on your horse.
Renoura doesn't try to kill anything. It works one step earlier, before the fly ever reaches him: it makes your horse hard for the fly to find in the first place. Different goal, different result.
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2. Flies don't find your horse by accident — they track him by scent. That's exactly what the oils disrupt.
Your horse's skin gives off a plume of carbon dioxide and other compounds that drifts on the wind.
Biting insects lock onto it through the scent receptors on their antennae and follow it straight to him.
Renoura's plant oils fill the air around your horse with aromas those receptors can't read through — so the fly loses the trail and drifts off somewhere else.
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The reason your last spray stopped working: the flies evolved past it.
The pyrethroid chemistry nearly every spray on the shelf is built on lasted three days on a horse in the 1980s.
Today it lasts about two hours — because the insects have spent forty years evolving resistance to it.
You weren't using it wrong. It was beaten before you bought it.
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A fly can adapt to a poison. It can't adapt to a horse it can't smell.
This is what makes the difference last. Insects evolve resistance to chemicals trying to kill them — it's an arms race they keep winning.
But there's nothing to out-adapt when an insect simply can't locate its target.
Renoura doesn't fight the fly. It takes your horse off her radar entirely.
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The oils aren't random — they're some of the most established botanical insect deterrents there are.
Citronella has been relied on as a plant-based repellent for over a century.
Litsea cubeba and clove are rich in citral and eugenol — two compounds research has repeatedly shown deter biting insects.
Lavender, peppermint, and thyme are long documented in the literature for the same.
These aren't novelty oils; they're the plant world's proven bug-deterrents.
