Can you tell me why leaf crops are supposed to respond better to liquid feeds than other crops.

Cheers, Eric99_2010

hat's in contrast to the opinion of many home gardeners who believe it's the preferred fertilization method. Even though the uptake is very efficient, it's not used to sustain the plant as the one & only source of fertilizer elements.

A search w/your favorite search engine should readily locate the why & how.

Foliar feeding is usually only used effectively to supply a few elements in ionic form (mainly N,Fe,Cu,Mn,Z), and only when plants that are able to provide a foliar pathway into the plant are growing so rapidly the nutrient stream cannot supply certain nutrients fast enough.

Remember - over-supplying a nutrient the plant doesn't need can be as bad as or worse than a deficiency. If you have a genuine deficiency, it's better by far to address it via the most efficient pathway - the root system. You can't make plants grow at beyond their genetic limitations, and supplying more of this or that than plants need is counter-productive. Trying to ensure the 12 elements you have control over are available in the soil at a favorable concentration and in the right ratio is about the best you can do.

I think one area where the hobby grower CAN effectively use foliar feeding is as a 'tell'. That is to say, after your lament and input about a particular symptom, I might suggest a foliar application of some chemical like Epsom salts or ferrous sulfate on part of the plant if I suspected a deficiency of Mg or Fe, for example. Applied one at a time and given a couple of days to work, you might be able to isolate one of several possible deficiencies. Of course, a soil test will usually provide the clues, but absent that, or when growing in containers foliar applications can sometimes be used effectively to tell you what you should be doing in terms of soil nutrition management.

Al

Take care.

Al

"The Reality
If these laundry lists look more like a multiple choice test rather than solid information, it's not surprising.
Foliar feeding is yet another agricultural practice best suited to intensive crop production under specific
soil limitations rather than as a landscape management tool. Thus, advertisers take great liberties with the
facts, often resulting in contradictory messages (note especially the recommended temperature
conditions!). Rather than individually refute the numerous errors in the claims, I'll explain when foliar
feeding might actually be beneficial." She then goes on to say, "Generally, the results suggest that foliar application of particular nutrients can be useful in crop production situations where soil conditions limit nutrient availability."

As I read the entirety of what she said, I find it quite similar to what I said, and I take her offering as pretty much pooh poohing the efficacy of the practice for the hobbyist.

Al