Powdery mildew?


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My Roma tomato plant has that few of these spots. Any advice? I tired 1 part milk 8 parts water saw it on YouTube
 

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You could also use Neem oil, it's actually designed to be used as an insecticide and fungicide. It smells kind of funky but it is a natural extract and virtually non-toxic.
 
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My Roma tomato plant has that few of these spots. Any advice? I tired 1 part milk 8 parts water saw it on YouTube
Milk is a sophisticated biological warfare food for opposing fungi, mainly because of its protien content which makes it both a food source for mildew eating pathology but also sticky as protiens inherently can be; as well as film forming, which presents across the surface of the leaf and thus disrupts the natural enzymes said fungi would normally use to penetrate or subsist upon a plant surface. It thinks it missed the parachute drop and landed on a cow so it will die. Well after the tricho and other fungi arrive it's spores may also be eaten as well of course.
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You spray, but also after every rain, and weekly at the most if other.,
 
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Advil is great for headaches but will do nothing about powdery mildew. Hydrogen peroxide works fairly well if mixed @1-2 cup per gallon of water but what works better is potassium bicarbonate. Neem Oil works good in early stages of powdery mildew. Copper based fungicides also work fairly well into the mid to late stages. But when anything is used BOTH sides of the leaf must be covered.
 
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Advil is great for headaches but will do nothing about powdery mildew. Hydrogen peroxide works fairly well if mixed @1-2 cup per gallon of water but what works better is potassium bicarbonate. Neem Oil works good in early stages of powdery mildew. Copper based fungicides also work fairly well into the mid to late stages. But when anything is used BOTH sides of the leaf must be covered.
I ment asprin lol
 
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Ok i will try hydrogen peroxide does it matter that ive already user, milk and aprin? i hope i dont kill my plant
 
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Ok i will try hydrogen peroxide does it matter that ive already user, milk and aprin? i hope i dont kill my plant
I might spray off any milk or aspirin before using it. I have not tried this but other gardeners I know have and it worked pretty good. Just dump a box of baking soda into a gallon of water and stir it up. What happens is the baking soda is highly alkaline and the mildew cannot live in an alkaline environment. You can use the hydrogen peroxide every day if you prefer. It only lasts 3 or 4 hours before it becomes just plain water.
 
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I haven't tested hydrogen peroxide on mildew but I think you can use the hydrogen peroxide (1 cup/gallon) safely as a foliar spray, and maybe even the 2 cup/gallon strength. You may even want to spray the leaves once a day for a few days. The peroxide will likely evaporate or oxidize before the sun breaks it down.
 
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Hydrogen peroxide works on the single cell "plants" like moss but does not hurt multicellular plants of a higher order. Not sure about the structure of mildew and it is far too late to start a google quest tonight. In fact it is used to help germination, and roots like the oxygen. It is watered down, like a teaspoon to a cup, or a tablespoon to a cup for stronger needs. Sodium percarbonate (like in Oxi-Clean)is a bad boy moss killer that is in part H2O2.

If I had a good source for potassium carbonate my soil can always use the potassium. I have sworn off copper, as it can build up and small amounts are toxic. Some countries (UK?) have begun to ban the copper based stuff.

The aspirin idea works, it is an acid and leaves a powder when dry. Fungi generally hate acids. I used 4 per gallon. Technically what you really want is called Salicylic acid not acetasalicylic acid (aspirin). It is a plant hormone that (in many plants) aids flowering and plant defenses through some cool chemistry.

Stolen:
"SA, for example, is a critical hormone that plays direct or indirect roles in regulating many aspects of plant growth and development, as well as thermogenesis and disease resistance".

Unfortunately it is also being listed by the EPA and examined to see if it is a tetragen. It also plays some roles in senescence, so I moved away from using it.

Lately I have been spraying potassium phosphites so they pretty much take care of the little problems too. They are absorbed by leaves and roots as potassium but the plant cannot use it so it knocks about inside as a systemic. This is extreme cool for a lazy gardener such as myself
 
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