Yogurt Whey as pest control

Has anyone here ever experimented with yogurt whey as pest control? We have cabbage worms on our tree kale every so often and we make yogurt once a week. I read about lactobacillus being used as cabbage worm control so I tried the whey. It worked, but I didn’t try different dilutions.

If someone could point me to literature about which plants can take this spraying, which pests it can prevent (have seen some literature on preventing vitis powdery mildew), and best dilution ratio I’d be very appreciative!

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Whey (but not milk) has been registered within the EU as a basic substance since 2016 – a food product that may also be used as crop protection.

According to the EU regulation, 6 to 30 liters of whey dissolved in 1000 to 1500 liters of water may be used for spraying one hectare. Whey consists of 6% of solids, so 1 liter of whey equals about 60 grams of dried whey powder. This corresponds to the 60 to 80 grams of active substance that may be present in the (liquid) whey.

Product (Application and concentration) Crop (greenhouse or outside) Fungus that causes powdery mildew Effect on powdery mildew Ref.
Milk (1-2x per week, different dilutions of 5-50%) Zucchini (greenhouse) Sphaerotheca fuliginea Progression is reduced by 90% when treated twice a week with a dilution of 3.8 – 11.4% 7
Milk (1x preventative before infection, 30% dilution) Zucchini (greenhouse) Podosphaera xanthii Reduction of progression by 88% 3
Milk (every 7-12 days and after 25mm of rain, 50% dilution) Pumpkin (Outside) Podosphaera xanthii Reduction of progression by 50-70% 8
Whey (2x per week, 10-30% dilution) Cucumber, zucchini (greenhouse) Podosphaera xanthii 71-94% less diseased plants depending on the whey concentration used 9
Milk (20 and 50 days after infection, 5.10 or 20% dilution) Soya bean (greenhouse) Erysiphe diffusa Reduction of progression by 40-72% 10
Milk (weekly, 10% dilution) Kale (greenhouse) Erysiphe polygoni DC. Reduction of progression by 30% 4
Milk powder (once every two weeks, 30g/L ~ 20% dilution) Grape (Viognier) (greenhouse) Erysiphe necator 15g/L reduces progression by 65-96%, 30g/L milk powder prevents powdery mildew contamination 1
Whey powder (1x every two weeks, 15, 30 or 45g/L) Grape (Viognier) (greenhouse) Erysiphe necator 15 and 30g/L reduce progression by 58-79%, 45g/L whey prevents powdery mildew contamination 1
Milk (1-2x every two weeks, 10% dilution, 300-600L/ha) Grape (Verdelho) (Outside) Erysiphe necator 79% of the harvest is acceptable compared to 87% when treated with sulfur (3g/L) 2
Whey powder 1-2x per two weeks, 45g / L, 300-600L/ha) Grape (Verdelho) (Outside) Erysiphe necator 76% of the harvest is acceptable compared to 87% when treated with sulfur (3g/L) 2
Milk (1-2x every two weeks, 10% dilution, 300-900L/ha) Grape (Chardonnay) (Outside) Erysiphe necator Reduces progression by 40% at harvest 11
Whey protein powder (1-2x per two weeks, 25g/L, 300-900L/ha) Grape (Chardonnay) (Outside) Erysiphe necator Reduces progression by 46% at harvest 11

Think that’s respective? 10% = 70, 30% = 94? Guess I can fool around with it this year with variables like “fresh whey at 10% dilution-30%, aged whey at 10-30%, previously frozen whey at 10-30%.”

I definitely have powdery mildew to spare if last year was any indication.

Lactoferrin appears to be the primary active component. It denature at 62 or 93 degrees C. fresh or frozen will not likely have any effect but ageing might just result in loss of the active ingredient.

How strange, my idea of using it for control was based on the use of Bacillus as a controlling agent, and I know dry yeast can easily be frozen then reactivated from a frozen state, but wasn’t sure if freezing my live cultures would be more detrimental. I guess you can use frozen yogurt as a starter so it should be fine (if lactobacillus can be a controlling agent). Regardless, there is at least one freezer stable component in the lactoferrin, so what’s the worst that can happen?

Lactoferrin is not a organism. its a protine

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We’re on the same page. I was saying:
I thought yogurt whey would work to control cabbage worms due to live bacteria.
The article you posted said, whey (probably cheese aka “sweet” whey) worked as a fungus control due to a non organism component lactoferrin.
Conclusion: yogurt whey may work to control fungus and cabbage worms due to multiple factors, so I will attempt using on pest insects and pest fungi with different dilutions.

Bacillus thuringiensis var. kurstaki is effective biological control
AKS Bt-k

Top 9 Bacillus Thuringiensis Kurstaki – Kitchen & Dining Features – SePole

I found a cheese maker about an hour and twenty minutes from my house that I’m going to buy whey from for the orchard and garden. Most of my trees are very young and haven’t shown any big disease issues, but I will let you know how it goes all the same.

The issue with whey is that it attracts other pests.

Interesting, what kinds?

Stefan Sobkowiak (The Permaculture Orchard) on Youtube sprays with whey and compost tea. He has lots of videos on the subject and explains the process very well i think. He has traps and things for all kinds of ‘pests’…that require no chemicals if that is a goal for someone.

There are some pests that those sprays dont affect… and he encourages wasps and birds and other insects such as spiders and beetles that will feed on those things. Whey and compost tea dont kill the natural predators.

Its a good alternative for someone that doesnt want to spray poison and toxins and chemicals on things that they eat.

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