Foliar feeding IS NOT a viable substitute for feeding thru the roots. It more marketing folksy stuff than anything else. If you have media or application limitations, then you need to correct that problem.
http://www.puyallup.wsu.edu/~Linda%20Chalker-Scott/Horticultural%20Myths_files/Myths/Foliar%20feeding.pdf
UB
https://www.rollitup.org/grow-journals/296617-afy-cutting-12-12-dwc.html
This plant was grown from a un-rooted cutting that was only 1.5" tall, dipped it in a fungi's rooting dip that I make up, then I put it in top of a 5 gallon bucket set up in a DWC.
this plant took six weeks from un-rooted to finished plant.
I trimmed the leaves and stem and weighted it wet but trimmed and the main cola was around 5.6oz and the two smaller ones were around 2.8 and 2.9 oz each. This is wet but trimmed. The scale is set to OZ so it is 11.85 oz wet and trimmed.
I challenge any one that does not believe that foliage feeding does not work to do this in six weeks. Take a cutting un-rooted and take it out to a finished colas with total weight, and post pics once a week just like I did, In fact I will do it again if need be.
So lets test this theory that this does not work and does not help a plant grow.
Also what the rest of the academic community thinks about this
Well I also read that pdf as well, she also said the foliar feeding did have a impact on non fruit bearing tress and bushes to correct micro nutrients deficiencies.
Her paper does not talk about fruit bearing trees or fruit bearing plants in general.
When I was younger working in tree orchards for apples, oranges, rubyred grape fruit, walnuts, and pecans from year to year when we could afford to foliar spray our harvest were 20% to 30% large by weight alone. So if there is no solid proof on file oh well, the yields speak in volume.
Here is a study with different resources disagree with the post you put up on my thread.
University of Tennessee - Prof. T.S. Osborne, Agronomist
"... research indicated that only 10 to 12 per cent of phosphorus fertilizers as taken up by plants in the first year; the rest was "locked in" the soil or washed away. Fertilizer applied to soil is largely wasted because it is either bound by soil particles or is washed out of the root zone. If chemical elements could go directly into leaves and bypass the wastefulness of soils, a tremendous saving would result.
The foliage of plants can take in nutrients much as roots can. Many nutrients are readily taken up by foliage, including bark of dormant trees; even at temperatures below freezing. Elements such as phosphorus, nitrogen, and potassium move both up and down from the point of application at rates similar to those following root absorption."
University of Michigan - Drs. Witter and Turkey as quoted in Readers Digest magazine
"... leaves lap up food like blotting paper and it spreads in a few hours from tip to root. In many cases, as much as 95 percent of the food sprayed on the leaves is used immediately by the plant, where under some conditions, the roots take up no more than 10 percent of the same amount placed in the soil."
Louisiana State University - Drs. A.L. Bertrand and L. L. Rusoff
"Trader elements were used to ascertain conclusively that plants absorb nutrients through their foliage, fruit, flowers, and twigs as well as their roots."
Agricultural Chemicals Magazine
"Phosphorus availability studies have given a ratio of 20 to 1 in favor of foliar feeding over soil feeding. There seems little doubt that where soil fixation exists, foliar applications of nutrients constitute the most efficient method of fertilizer "placement" and with plants of sufficient leaf area, foliar feeding with ALL the elements can make a significant contribution toward the total nutrient requirement."
Ontario Agricultural College - Dr. T.E. Bates
"We increase corn yields 7 bushels per acre at five different locations with liquid fertilizer placed directly with the seed. The corn also received the recommended amounts of fertilizer in a band. The most startling difference is in the size. Some fields were half again as tall two weeks after the core cam up."
Big Farmer Magazine
Dr. S.H. Wittwer of Michigan State
"Farmer should fertilize according to soil test recommendations, follow with 'starter solutions' or 'pop-up' fertilizers and finish the job with foliar applications."
ATTRA - National Sustainable Agriculture Information Service
http://attra.ncat.org/attra-pub/foliar.html
http://www.growersmineral.com/crops/...iar-feed-plans
