Zone 6B here. Used MySoilTestKits for the soil analysis and got a Boron reading of 0.06PPM (0.2-0.6PPM) is optimal so I’m extremely low. I purchased Go Garden 20% Boron micronutrient fertilizer but struggling on how to Apply. To even attempt the drip rate (correcting soil) you’d have to figure out what 150 gram per acre would amount to per 150Sqft for my tree which is too small for me to measure. So my other option would be to use the Foliar option on the label which would be 1g per liter of water but this is also too small for me to measure without such an accurate scale. Question is… what should I do? I know Boron can go from depleted to toxic extremely easy. Should I skip on treating the soil and try to get a cheap milligram scale for foliar spray? When should I spray it/how.
I would think the package would have directions for when to spray or treat. I will say that it’s a bit important what kind of soil you have before deciding on foliar vs adding it to the soil.
I have always used mule team borax. My soil has plenty but it’s high pH and the trees have trouble getting it, so I have used it as a spray. I always mean to do it more than once, but never actually manage it and it ends up being at the end of the season. It was recommended to me (by reading random threads on this site) to apply at tight cluster, but this is the spray I never manage
How old is the tree? How alkaline is your soil? Where in 6B are you? What kind of soil do you have? is it clay, sand, loamy?
As for how to measure small amounts: You double dilute if it’s liquid- if it stores, you can keep the half part strength and then use it next time you need to. Also, if your soil is that low on boron, do you not see issues on your landscape plants? would they not like some boron?
If it’s powder, you mix it into another powder and then you have to do a bit of math to get the right amount. if you have fertilizer powder or anything else you plan to supplement with - people use kelp or things- this works well. You could also be cheap like I would and get some dirt from the yard, dry it out, mix with the borax at known weights and then sprinkle the dirt +borax around the dripline at the correct rate.
Just one guys opinion. I’d start with 1/4 tsp per tree. Dissolve it in a half gallon water and water equally out to drip line. Then do foliar spray at petal drop. Should say on your package to mix foliar spray but go easy on it.
The only directions on label are this.
For foliar spray, dissolve 1 gm/liter of water and apply to both sides of the leaf. For drip irrigation, use 150g per acre. Suitable for use on various crops, such as Pomegranate, Grapes, Citrus, Mangoes, Cashew, Grams, Peas, Beans, Paddy, Wheat, Soya, Cotton, Sunflower, Piper Mint (Mentha), and Flowers. Ideal for a wide range of crops, including Tomato, Okra, Brinjal, Chilly, Gourds, Beans, and more.
My soil type is Allenwood Gravelly Silt Loam rich in clay. Ph test came back at 6.06 PPM. Tree is Semi Dwarf Reliance about 5 years old now.
I also use 20 Mule Team Boraxo and just sprinkle the recommended amount on the ground around my fruit trees, including peach, plum, cherry, and apple. I’m in the wet Pacific Northwest, where the soil is chronically low in boron due to leaching. It’s recommended to apply boron every spring here, but in drier areas every 3 years is supposed to be OK. The amount to apply should vary with location.
Just thought of something. Make sure you’re reading your soil test properly. Is there a drop down tab that allows to select lbs per 1,000 sq ft, lb per acre, and ppm. You want to be on the ppm view to read the analysis as your recommended levels are in ppm.
I went through this before and realized that test I used was showing lb per 1,000 sq ft by default for the analysis not just recommended applications. Really had me thrown off and I think it will to a lot of people. Switched it to ppm and it all made sense.
Not saying this is your case but with boron that low it could be.
Tests don’t matter so much, what matters is what your tree tells you. Have you observed a deficiency?
When treating the soil it is very unlikely you will cause damage if you are conservative in your app. I like the adage, “sprinkle it like fairy dust”.
Or you could run with CHAT GPT… For a very boron-deficient garden soil, the common extension recommendation is about 1 tablespoon of borax per 100 square feet, dissolved in water and applied evenly, then worked into the soil. Oregon State and Maryland Extension both give essentially that rate for low-boron soils.
This is from the OSU source… A note about boron
Many soils in Western Oregon are deficient in boron (B). Several crops (cabbage, broccoli, cauliflower, caneberries, strawberries, beets, carrots, etc.) can benefit from an application of boron.
If the soil test for boron is less than 1 ppm, apply household or agricultural grade borax (11% B) at the rate of 1 tablespoon per 100 square feet where boron-requiring plants will be grown. Apply the borax evenly and mix thoroughly with the soil. it may be easier to dissolve 1 tablespoon of borax in 1 gallon of water and apply the solution evenly with a sprinkling can. Apply 1 fluid ounce of solution per plant. You can find borax in the cleaning supplies section of most grocery stores.
Be careful! Excessive quantities of boron are highly toxic to plants, especially young bean plants. One application should be sufficient for up to three years or until another soil test.
Recs for peach trees are about the same.
On PEI, at about 46 degrees north, I take a 5 gallon bucket (imperial gallon) of wood ash and spread it out on dry cement. Then I add a heaping tablespoon of borax from the laundry isle and mix well. Each tree gets a mug full at the drip line, leftovers go to pears and beets. Seems to work here.