Milk Solution or Copper Sulfate?

[NooraK]

I believe we've been hit with blight:







I've searched a bit, and found two solutions to attempt to fight the issue. One is a milk solution, the other is to use copper sulfate, or a copper & lime mixture (dissolved in water).

While I would like to stay organic, I am not completely opposed to non-organic methods, and from what I understand, the copper sulfate could go either way. The biggest concern seems to be its build up in the soil.

Would any of you recommend one method over the other? I was thinking of starting with one application of the copper and then continuing with the milk solution.

[lorax]

I use very low doses of copper sulfate (1 tsp in 1L) right in the milk solution, and it works wonderfully for me. There isn't enough copper that way to accumulate in the soil, and the one-two punch seems to knock the blight right off the tomatoes and prevent it spreading.

[NooraK]

Thank you, that sounds like the perfect solution!

[gardenbean]

Thanks for the pictures. So that is what blight looks like. How does a tomato plant get blight?

[lorax]

It's bacterial, and can be either airborne or soil-borne; normally appears after a period of heavy rain (which splashes it up out of the soil and onto the plant).

[Rogue11]

I use very low doses of copper sulfate (1 tsp in 1L) right in the milk solution, and it works wonderfully for me. There isn't enough copper that way to accumulate in the soil, and the one-two punch seems to knock the blight right off the tomatoes and prevent it spreading.

Silly question, where do you get copper sulfate?
I have used milk solution for powdery mildew before; you think the mix will work on that too?
Thanks.

[NooraK]

I use very low doses of copper sulfate (1 tsp in 1L) right in the milk solution, and it works wonderfully for me. There isn't enough copper that way to accumulate in the soil, and the one-two punch seems to knock the blight right off the tomatoes and prevent it spreading.

Silly question, where do you get copper sulfate?
I have used milk solution for powdery mildew before; you think the mix will work on that too?
Thanks.

Hubby brought some home from the home improvement store.

[NooraK]

Ok, so looking at the bottle of stuff Hubby brought home, it actually says "copper ammonium complex". How different is this from copper sulfate? The container does say it is a fungicide.

[lorax]

I buy copper (II) sulfate at my local farm supply/agribusiness store, but I could also get it at the chemical store - it's cheaper at the ag store. It pays to phone around.

Copper-ammonium complex will work on fungal diseases fairly well but it's terrible against bacterial blights - the difference is in the ammonium (a hydrogenated nitrogen compound) bonded to the copper ions, rather than sulfate (an oxygenated sulfur compound). However, give it a shot mixed with milk - at the very least it will take care of the mildew problem.

[sixshooter]

What exactly is the milk solution and how do you apply?

[gardenbean]

lorax-thanks for describing what blight is. I think I may have that on one of my tomatos on her bottom leaves. I would prefer at first to try the milk solution. Would that be the one where it's 9 parts milk to 1part water?

[graham]

Lorax-

How do you apply your solution? Got more rain coming here. Thanks.

[NooraK]

Lorax-

How do you apply your solution? Got more rain coming here. Thanks.

We got a pump sprayer like this one:

[lorax]

I have a simple spritzer bottle, although if the weather continues to be ugly the way it has recently, I'll be upgrading to a pump sprayer.

And yes, 9 parts water to 1 part milk, with 1 TBSP copper sulfate.