Foliar spray application rates (fertilizer/minerals)

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Shule
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Foliar spray application rates (fertilizer/minerals)

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Post: # 57158Unread post Shule
Fri Nov 12, 2021 12:45 am

This thread is for declaring (and experimenting with) foliar spray application rates of fertilizer, minerals, and such, since they can be pretty hard to find or convert, sometimes. Sources for information are below. Feel free to reply with more information, if you know it! My pump sprayer is 51oz (although it's advertised as 48oz, though it has a marker at the 48 point); so, I'll try to give rates for the standard gallon of water, as well as for 51oz (fluid ounces) of water. If percentages are given, there's a conversion guide below.

Warnings: These measurements are untested, unless mentioned otherwise (and then only anecdotally). They may or may not be accurate. You use this information at your own risk, for all items, tested or not. Make sure to do foliar sprays when the sun isn't out. Wear a mask/goggles for some kinds, for safety reasons, and don't spray when other people are close to you. Just because I list something that doesn't mean I recommend it. Some of these things you obviously wouldn't want to put in a pump sprayer if you value it: e.g. anything that doesn't completely dissolve, as well as cow dung and probably other natural things .

Ammonium sulfate (21N-0P-0K-24S): 1-3tbsp per gallon
Calcium acetate (Foliar sprays on rice are said to be helpful when the ozone is higher, and usable on many garden plants. Is said to be able to be used in larger amounts than calcium chloride, as a foliar spray, so if you use the same amount, you're probably safe. You can make it easily at home with vinegar and something containing calcium carbonate, such as eggshells or limestone, or else slaked calcium oxide. See sources 14, 15, and 18 for ideas on application rates.)
Calcium chloride (Small amounts are needed to avoid burning, I've read.) See source 18 for rates mentioned in an experiment and the results.
Calcium nitrate (15.5N-0P-0K-19Ca): 2-4tbsp per gallon (not tested); 1tbsp per 51oz (tested; works great, and can be done once a week or two, although if you do it too many weeks in a row, you might get issues; 2tbsp is enough to slightly burn an outdoor grapevine, though)
Copper sulfate [hydrous] (25.47Cu-38.47S): 2%, or 5.12 tbsp per gallon, twice a season, for deficient wheat (not tested; sounds like a lot; be careful, because too much copper can stop plant roots from growing); 2.0318 tbsp per 51 oz twice a year (not tested); for tomatoes, as a fungicide, they say to use 4 teaspoons per gallon (not tested) every 7-10 days, or 1.5936 teaspoons per 51oz
Cow dung (fermented): Not sure. See source 16. I imagine you'd only use this on ornamentals, if at all.
Dissolved eggshells: See source 17.
Epsom salt (9.8Mg-13S): 2tbsp per gallon once a month, for most plants (not tested); 2.39 teaspoons per 51oz (not tested)
Fish emulsion: 1-3tbsp per gallon; 1.195-3.585 teaspoons per 51oz (not tested). See source 19. I'm not sure that you can use this in a pump sprayer.
Greenway Biotech's Pepper and Herb Fertilizer (11N-11P-40K plus micronutrients): 2.5 grams or ~0.5 tablespoons per gallon (not tested); ~0.5975 teaspoons per 51oz (not tested); see source #22 for precautions (water after application, and do not apply when it's over 65 degrees F. outside).
Greenway Biotech's Tomato Fertilizer (4N-18P-38K plus micronutrients): 2.5 grams, or ~0.5 tablespoons per gallon (not tested); ~0.5975 teaspoons per 51oz (not tested); the source #21 for precautions (water after application, and do not apply when it's over 65 degrees F. outside).
Iron sulfate heptahydrate (20Fe-12S): 1-2tbsp per gallon (not tested); 1.195-2.39 teaspoons per 51oz (not tested).
Manganese sulfate (31Mn-18S): ¼ to ½ teaspoon per gallon (not tested); I burned plants badly when I tried a foliar spray of this and monopotassium phosphate in 2015, but I probably used too much of one or both of them (I didn't put them in the same bottle, but I sprayed both within a day or so); however, in 2022, I experimented with 1 tablespoon of manganese sulfate in 51oz of water (I didn't also spray monopotassium phosphate), and it just made the plants greener and made them look a little bit stressed.
Miracle Gro All-purpose water-soluble fertilizer (24N-8P-16K-0.02B-?Cl-0.07Cu-?EDTA-0.15Fe-0.05Mn-0.0005Mo-?Na-?S-0.06Zn): 1 level tbsp per gallon every one to two weeks (not tested); 1 semi-heaping teaspoon (1.195 teaspoons, or 0.3984 tablespoons) per 51oz (tested); only for outdoor foliar sprays, according to the instructions on the box. Warning: The small end of the scoop is only ½ teaspoon, and the large end is 1½ tablespoons (don't expect a teaspoon and a tablespoon).
Monoammonium phosphate (12-61-0): 1-3tbsp per gallon (not tested); 1.195-3.585 teaspoons (not tested)
Monopotassium phosphate (0-52-34): 2-3 tbsp per gallon; 0.7968-1.1952 tbsp (2.39-3.586 teaspoons) per 51oz
Potassium nitrate (13-0-44): 9.6 tbsp per gallon (untested; needs to be agitated or something before spraying to mix properly with the water; in theory, using the same ratio as potassium sulfate should get you a similar amount of potassium; they're probably adding more for increased benefit of extra nitrogen balanced with the potassium); for mango trees, use a 1% to 4% (you may especially want to read the sources about this one as there are special instructions).
Potassium sulfate (0N-0P-53K-17S): 2-3 tbsp per gallon; 0.7968-1.1952 tbsp (2.39-3.586 teaspoons) per 51oz. I've tested a solution, but I don't remember if it was according to these measurements offhand. I probably mentioned how much I used on my growlog.
Sea minerals: 1 teaspoon per gallon (0.13%). It would clog a pump sprayer eventually. See source 20 for more information.
Seawater: Assuming the seawater is 3.5% sea minerals . . . I'm not sure the rate. It would probably clog a pump sprayer eventually. Should be essentially the same thing as sea minerals, with added beneficial bacteria (and possibly harmful pollution).
Urea (46-0-0): 0.5% to 2% solution.
Wood ash and sour milk: Not sure. See source 16.
Zinc sulfate monohydrate (16.5S-35.5Zn): Foliar spray not recommended for all kinds of water (since it reacts instantly with at least my tapwater to form a solid white rock-like substance). 1-3tbsp per gallon (not tested); 1.195-3.585 teaspoons (not tested)


Percentage guide:
Note: 1 tablespoon is 0.0039 gallons. There are 256 tablespoons in one gallon. 1 teaspoon is 0.0013 gallons. There are 768 teaspoons in one gallon. 1 teaspoon is 0.167oz. 1 tablespoon is 0.5oz.

Teaspoons per gallon to percentage:

• ⅛ teaspoon per gallon is 0.0162%.
• ¼ teaspoon per gallon is 0.0325%.
• ½ teaspoon per gallon is 0.065%.
• 1 teaspoon per gallon is 0.13%.
• 2 teaspoons per gallon is 0.26%.

Tablespoons per gallon to percentage:

• 1 tablespoon (3 teaspoons) per gallon is 0.390625%.
• 2 tablespoons (⅛ cup) per gallon is 0.78125%.
• 3 tablespoons per gallon is 1.171875%.
• 4 tablespoons (¼ cup) per gallon is 1.5625%.
• 5 tablespoons per gallon is 1.953125%.
• 5⅓ tablespoons (⅓ cup) per gallon is 2.08_3% (by _3 I mean 3 repeating).
• 6 tablespoons per gallon is 2.34375%.
• 7 tablespoons per gallon is 2.734375%.
• 8 tablespoons (½ cup) per gallon is 3.125%.
• 9 tablespoons per gallon is 3.515625%.
• 10 tablespoons per gallon is 3.90625%.
• 10⅔ tablespoons (⅔ cup) per gallon is 4.1_6%
• 11 tablespoons per gallon is 4.2996875%.
• 12 tablespoons (¾ cup) per gallon is 4.6875%.
• 13 tablespoons per gallon is 5.078125%.
• 14 tablespoons per gallon is 5.46875%.
• 15 tablespoons per gallon is 5.859375%.
• 16 tablespoons (1 cup) per gallon is 6.25%.

Percentage to tablespoons per gallon:

• 0.05% is 0.128 tablespoons per gallon.
• 0.1% is 0.256 tablespoons per gallon.
• 0.2% is 0.512 tablespoons per gallon.
• 0.3% is 0.768 tablespoons per gallon.
• 0.4% is 1.024 tablespoons per gallon.
• 0.5% is 1.28 tablespoons per gallon.
• 1% is 2.56 tablespoons per gallon.
• 1.5% is 3.84 tablespoons per gallon.
• 2% is 5.12 tablespoons per gallon.
• 2.5% is 6.4 tablespoons per gallon.
• 3% is 7.68 tablespoons per gallon.
• 3.5% is 8.96 tablespoons per gallon.
• 4% is 10.24 tablespoons per gallon.
• 4.5% is 11.52 tablespoons per gallon.
• 5% is 12.8 tablespoons per gallon.
• 5.5% is 14.08 tablespoons per gallon.
• 6% is 15.36 tablespoons per gallon.
• 6.5% is 16.64 tablespoons per gallon.
• 7% is 17.92 tablespoons per gallon.
• 7.5% is 19.2 tablespoons per gallon.
• 8% is 20.48 tablespoons per gallon.
• 8.5% is 21.76 tablespoons per gallon.
• 9% is 23.04 tablespoons per gallon.
• 9.5% is 24.32 tablespoons per gallon.
• 10% is 25.6 tablespoons per gallon.

For teaspoons/tablespoons per 51oz:

Note: 1 teaspoon is 0.167oz. 1 tablespoon is 0.5oz. 51oz is 305.38922155688622 teaspoons. 51oz is 102 tablespoons.

Teaspoons per 51oz to percentage:

• ⅛ teaspoon per 51oz is 0.04084967320261%.
• ¼ teaspoon per 51oz is 0.08169934640522%.
• ½ teaspoon per 51oz is 0.16339869281045%.
• 1 teaspoon per 51oz is 0.32679738562091%.
• 2 teaspoons per 51oz is 0.65359477124183%.

Tablespoons per 51oz to percentage:

• 1 tablespoon per 51oz is 0.98039215686274%.
• 2 tablespoons (⅛ cup) per 51oz is 1.96078431372549%.
• 3 tablespoons per 51oz is 2.94117647058823%.
• 4 tablespoons (¼ cup) per 51oz is 3.92156862745098%.
• 5 tablespoons per 51oz is 4.90196078431372%.
• 5⅓ tablespoons (⅓ cup) per 51oz is 5.22875816993464%.
• 6 tablespoons per 51oz is 5.88235294117647%.
• 7 tablespoons per 51oz is 6.86274509803921%.
• 8 tablespoons (½ cup) per 51oz is 7.84313725490196%.
• 9 tablespoons per 51oz is 8.82352941176470%.
• 10 tablespoons per 51oz is 9.80392156862745%.
• 10⅔ tablespoons (⅔ cup) per gallon is 10.45751633986928%.

Percentage to tablespoons per 51oz:

• 0.5% is 0.51 tablespoons per 51oz.
• 1% is 1.02 tablespoons per 51oz.
• 1.5% is 1.53 tablespoons per 51oz.
• 2% is 2.04 tablespoons per 51oz.
• 2.5% is 2.55 tablespoons per 51oz.
• 3% is 3.06 tablespoons per 51oz.
• 3.5% is 3.57 tablespoons per 51oz.
• 4% is 4.08 tablespoons per 51oz.
• 4.5% is 4.59 tablespoons per 51oz.
• 5% is 5.1 tablespoons per 51oz.
• 5.5% is 5.61 tablespoons per 51oz.
• 6% is 6.12 tablespoons per 51oz.
• 6.5% is 6.63 tablespoons per 51oz.
• 7% is 7.14 tablespoons per 51oz.
• 7.5% is 7.65 tablespoons per 51oz.
• 8% is 8.16 tablespoons per 51oz.
• 8.5% is 8.67 tablespoons per 51oz.
• 9% is 9.18 tablespoons per 51oz.
• 9.5% is 9.69 tablespoons per 51oz.
• 10% is 10.2 tablespoons per 51oz.

Sources:
1. https://www.greenwaybiotech.com/product ... um-nitrate
2. https://homeguides.sfgate.com/can-put-m ... 75878.html
3. https://www.gardeningknowhow.com/garden ... 0flowering.
4. https://www.publish.csiro.au/an/EA9800717
5. https://www.greenwaybiotech.com/product ... us-sulfate
6. https://www.greenwaybiotech.com/products/zinc-sulfate
7. https://www.greenwaybiotech.com/product ... er-soluble
8. https://www.greenwaybiotech.com/product ... ate-0-0-53
9. https://www.ehow.com/how_7336193_apply- ... trees.html
10. http://www.brixbounty.com/wp-content/up ... n-2016.pdf
11. https://onlinelibrary.wiley.com/doi/ful ... /aab.12653
12. https://www.ams.usda.gov/sites/default/ ... cetate.pdf
13. https://growingorganic.com/diy-guide/ho ... m-at-home/
14. https://www.ourfigs.com/forum/figs-home ... um-at-home
15. https://www.agrian.com/pdfs/current/10_ ... bel3.pdf16. https://file.scirp.org/Html/3-2170238_69571.htm
17. https://www.gardeningknowhow.com/garden ... ilizer.htm
18. https://www.researchgate.net/publicatio ... Mill_fruit
19. https://www.trees.com/gardening-and-lan ... of%20water.
20. https://seaagri.com/foliar-application/
21. https://www.greenwaybiotech.com/collect ... fertilizer
22. https://www.greenwaybiotech.com/collect ... fertilizer
Last edited by Shule on Thu Jun 30, 2022 6:47 pm, edited 4 times in total.
Location: SW Idaho, USA
Climate: BSk
USDA hardiness zone: 6
Elevation: 2,260 feet

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Whwoz
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Re: Foliar spray application rates (fertilizer/minerals)

#2

Post: # 57159Unread post Whwoz
Fri Nov 12, 2021 2:20 am

Love your work @Shule, although I don't see the value in adding sea water / minerals which is mostly salt, but then other places maybe deficient in Sodium or chlorine, Oz certainly is not.

Fermented cow manure is generally referred to as a manure tea, very beneficial to a wide range of plants.

A note for other Aussies who read this, don't forget that the Australian tablespoon is four teaspoons (20 ml), not three (15 ml) like the American tablespoon is.

mama_lor
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Re: Foliar spray application rates (fertilizer/minerals)

#3

Post: # 57160Unread post mama_lor
Fri Nov 12, 2021 3:32 am

That's a lot of work into that list. I feel I should warn against components that raise the pH (like wood ashes), the final solution should be on the acidic side to be effective, and one should also apply very early in the morning (simply because it will not be very efficient otherwise).

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Shule
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Re: Foliar spray application rates (fertilizer/minerals)

#4

Post: # 72747Unread post Shule
Thu Jun 30, 2022 4:13 am

@Whwoz
Speaking of salt, I was reading the other day about how foliar sprays of acids can make plants more salt tolerant, increase certain kinds of growth, and things. It was very interesting. I don't know the application rates, yet (I'm sure too much would be deadly to the plant), but I read about that for citric acid, ascorbic acid, and even acetic acid.
Location: SW Idaho, USA
Climate: BSk
USDA hardiness zone: 6
Elevation: 2,260 feet

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