Yeah, foliar feeding for just about anything is a crock, always has been. There are no times when the plant would benefit more from fertilizer sprayed on the leaves than having that same mix poured onto the roots.

Its simple common sense, really. The plant evolved to take in nutrients through it's roots, not it's leaves. If by some weird coincidence it can take some in through it's leaves, then thats purely an accident, and the plant is not "designed" to be able to do it that way.

IMO, its honestly just a diversion to give new growers something to do so they don't over-baby their plants. They always feel like they should be doing SOMETHING on a constant basis, and foliar feeding is a nice, mostly harmless distraction (except for when it causes mold, mildew, and other moisture related problems) that keeps the busy bodies from overwatering or otherwise damaging the plant.

Edymnion,
Glad to read your comments. I support Foliar feeding in certain cases. See article below. Of course you can find many scientific studies on the web.
But then I support fertigation.
But I believe everyone should have their opinion and stick with it. Because only each of us knows from experience what worked for them and what was a waste of money.
I'll leave you with one thought: Spanish Moss
Thanks for your comments,
Bob

Here is a link that might be useful: Basic article about foliar feedings

Foliar feeding to correct things like iron deficiency are useful...micronutrient applications for emergency correction...etc.

Outside of that, though...unless you have some severely short season to grow/harvest time and soil-feeding can correct these deficiencies.

NPK foliar feeding is almost useless except in emergency deficient or time-sensitive-harvest crops because you can't get a lot of use out of it without burning plants.

Well said.
I know that the following is obvious, but I almost missed it one year:
If someone has micronutrient deficiencies and uses Osmocote or other fertilizers, like plain 10-10-10, which does not contain micronutrients, the micronutrients deficiencies will not be corrected through the exclusive use of these fertilizers.

Edymnion is right on in his comments.

Foliar feeding is a limited, inefficient means of fertilizing.
If a plant *does* respond to foliar feeding, it should be given a proper dose of nutrients
via the prefered, more efficient route - root delivery. I feel the same about foliar feeding
as I do about 'misting' - it has such narrow, limited usefulness that it's a waste of time;
and, in some cases, the lingering moisture can prove harmful.

Of course, I use a fertilizer which contains all the micronutrients.

Josh

Bugbite, I read the opening to that second article you linked, and it basically said "In times where a plant doesn't have roots, then foliar feeding is a good idea". If the plant is damaged or stressed to the point it can no longer feed properly, then yes, foliar feeding can keep it alive long enough to heal itself. But thats cherry picking some very unusual situations to try and support the position.

To use an analogy, you can feed a human with a nutrient drip solution and an IV bag. It'll keep them alive, and its very handy for when they're too injured to eat, but for a healthy individual you are always better off giving them a plate and telling them to eat it. Same with plants. A normal, healthy, non-moss plant (since moss tends to grow in nutrient poor environments and be very low to the ground, they would naturally be better adapted to absorbing nutrients that fall onto them through the leaves than a pepper or a tree would be) will always do better feeding through the roots than the leaves.

As for the studies mentioned at the end of the article, I would question their methods. Says it was proven that foliar fed plants did better than controls. What were the controls? If both plants got the same feeding schedule, and then one got extra food through it's leaves, of course it would do better. Pour that extra food down on the roots though and I'd wager the rooted plant would do better than the foliar.

I mean, if for nothing else, foliar feeding relies almost entirely on whatever nutrients just happen to essentially soak into the leaves (technically its what would be pulled into the stomata by capillary action) as opposed to the active feeding system provided by the roots.

Heh, to use another analogy for that one, it is possible to get drunk by absorbing alcohol through your skin. You fill a bathtub with booze and lay in it long enough, and you will get drunk off it. Its still a hell of a lot more efficient to just drink it though.

That is what page 20 of the article I sited at the top of the page said.
That article was well done.
Anything in the article that you folks disagreed with?