applying boron for tomatoes

[TechGuy]

I had a leaf tissue analysis done by state lab and my tomatoes ranged from 24-30 ppm boron. I guess the best range is 30-80 according to borax.com.

my local extension agent told me to use 2 teaspoons per gallon for foliar application. normally, I do small tests but I was seeing some questionable color in leaves so I overvalued the advice and killed all the plants I sprayed with the recommneded mix.

now I am working with state lab to find out how much boron product and what type to use per gallon for watering into soil and also what mix to use for a foliar application per gallon. currently they offer rates for using drip tape and acres. they have not given me any info yet.

Can anyone recommend specific product to use for foliar applicaiton per gallon along with rate?

I am looking for both soil and foliar depending on if its been raining a lot or not. I already use a small amount of borax in my initial starter mix but I think when plants get bigger and go deeper (or I used straw bales) I am not getting enough coverage

[Gardeneer]

I have never paid much attention to Boron in fertilizers. But I think MG blue has boron it.

BTW: I had some standard soil test done by the county AG office. I don't recall the did mentioning anything about Boron.

[RayR]

Did your plants show boron deficiency symptoms? Why would you even need to do a foliar application? Sound like a dangerous thing to do, Boron is used as a foliar herbicide since it's highly toxic to plants in high enough doses. Looks like you found what the toxic amount is for tomato plants using borax. Too much boron in your soil will also be toxic too, not something to use liberally for sure.

[Gardeneer]

Originally Posted by RayR

Did your plants show boron deficiency symptoms? Why would you even need to do a foliar application? Sound like a dangerous thing to do, Boron is used as a foliar herbicide since it's highly toxic to plants in high enough doses. Looks like you found what the toxic amount is for tomato plants using borax. Too much boron in your soil will also be toxic too, not something to use liberally for sure.

Good points.
Boron, as I understand, is a a trace element, in the 3rd category;

FIRST : NPK
SECOND: Mg, Ca, Fe, S,
THIRD: The rest of A to Z.

I could be wrong.

[MissS]

High doses of boron is lethal to plants. I used some on an anthill mixed with sugar once and the grass did not grow back for three years. It did kill the ants though.

I have only once added boron to a garden and I used 1/4 of a teaspoon per gallon and the plants did very well with that.

I hope that this is of some help.

[Greatgardens]

Just curious -- what was the boron product/source that you used?
GG

[zipcode]

2 teaspoon per gallon should be in about 0.3%. Shouldn't be lethal. Recommended dose is 0.1-0.3. So about one teaspoon should be best. You didn't say what you sprayed with though, usually should be borax.
It's not normally needed in soil unless you are 'power growing'.
Very important element though, with big role in fruit set and ber.

[MissS]

Borax

[RayR]

Waiting for TechGuy to respond. I'm curious as to what the lab sees as sufficient boron levels in the tissue analysis for tomato and what reasons why there may be a lack Boron in his soils. I know micronutrients like Boron are important and there are limiting factors that lead to very low levels of B in some soils, but there are always plant symptoms that reflect a deficiency and a need to correct it.
Everything I've read about Boron includes the same warnings about the narrow margin between B sufficiency and toxicity.

[AKmark]

I forward my results to Hydro Gardens, they deal with thousands of commercial growers, and Mike is the man. You were so close I would do nothing, but that is only my two cents,if your lab bar chart shows it is an acceptable range that is.

[TechGuy]

the lab guy was vague on the levels when I cited the borax web site numbers. i don't think he thought it was a big issue. he was going to get me their calculations per gallon for borax or other product but I have not heard from him yet

to GG, i used borax

[Dak]

I add Borax to my soil amendment, 10% or 0.15lb to 1,000 feet as per my soil guy.