If you have had a soil test done, that should be answering your questions, not us :-)

Understanding if, when and how to fertilize is a common issue that many find confusing and that confusion is not helped by the fertilizer manufacturers with their constant advertising that seems to imply that you cannot have a successful garden or harvest without the need for routine fertilization. That is simply NOT true!!

If I come across as too 'school teacher-ish', please excuse me but much of the confusion comes from the popular usage of the term "plant food" when referring to a fertilizer. Fertilizer is not plant food - plants manufacture their own food through the process of photosynthesis, converting oxygen, sunlight, water and nutrients pulled from the soil into the starches, sugars and proteins they need for healthy growth and to produce flowers and fruits.

Ideally, plants get all of what they need in the way of nutrients from the soil. All a fertilize does is to supplement nutrients that may be missing or deficient in the soil. That is why a soil test is typically recommended before applying any fertilizer - to assess what, if anything, is missing or deficient. If nothing is, no fertilization is necessary.

Fertilizing when it is unnecessary can cause as many problems as not fertilizing when it is called for. It can lead to rampant growth that is more vulnerable to pests and diseases and less tolerant to weather extremes; it can contribute to ground water pollution; and if applied incorrectly, can actually deter flowering and fruiting.

Long story short, applying fertilizer should never be considered a routine garden chore but instead one that is done only when determined to be necessary by a soil test or by the plants themselves demonstrating a nutrient imbalance. The only exception is a plant grown in a container - these have no access to garden soil or the nutrients it contains and so must be supplemented by fertilizers.

FWIW, trees and shrubs established in the landscape and growing and producing well may never need any supplemental fertilization. And this is even more likely the case when they are routinely mulched with some sort of organic material: compost, composted manures, leaves or bark or wood chips.

^^ Great, well-thought-out post -- thank you!

So gardengal my request was to hear feedback and information as to how folks are fertilizing their trees. You read my post improperly. I'm not asking for an education, I already know everything you tried to school me on, well at least the things you said that are correct. If my post was "I don't understand fertilzer, please help me", your response would have been more appropriate. I'll just point out a couple flaws in the various premises that you are operating from because it would take to long to refute everything. 1. Your idea that a soil test is the complete answer to understanding your trees requirements now and in the future ... and if one is done, that there is no need to be discussing fertilizer on a fruit tree forum is pretty short sighted and condescending ... but I'll let that slide and get to the meat and potatoes of why you are wrong about this. Anyone with field experience, or common sense, knows that the soil conditions and nutrient levels over an area of say an acre, can vary quite substantially. Factors such as landscaping and shifting of land by a bulldozer years ago or natural actions such as erosion, mudslides, geological formations or anomalies, changes in elevation (like a sloped hillside that fades into a flat riverbed area), a large tree having occupied a space 20 years ago, and a whole slew of other reasons can contribute to variances in soil compostion in a given plot of land that is being planted out with fruit trees. 2.) It is a well known and understood fact that a fruit tree will pull and use NPK and other nutrients like calcium from the soil over the years and that in many instances this will need to be replenished to sustain healthy growth and production ... this process of adding an ongoing supply of nutrients to our trees is a process called "Fertilization". In five years, should I dig down into the rootsystem 2-3 ft. and send a soil sample to my local extension. No, of course not. If the tree has yelloweing leaves or slow growth, and other factors like disease have been considered and eliminated, then I add nitrogen appropriately ... and so on. 3.) Dwarfing rootstocks, which many of us use, create a condition that is not unlike a "big container". Since you thankfully acknowledge that container plants need fertilization, I can now conclude that you will understand the concept that a dwarfing rootstock by by its very design, is less vigorous and therefore less able to search out nutrients and water ... and may need a little help either now, or down the road once it has sucked up all of the available stuff within its limited capable range.

You remind me of the nutritionist that says as long as you eat 3 square meals daily you'll be healthy. Well some folks are not satisfied with medocrity ... they want better results, so they go to the gym and take supplements (fertilizer) and jack up their protein intake. Incredibly, they put on more muscle, look better, and are healthier than the couch potato that has all of the nutrients he needs.

So for those of you that understand fertilizer, wondering how you are doing it.

If you already know all of the above, what was the point in asking what other people on other planting sites with different soil mineral levels and other circumstances are doing? Sampling and testing your own particular soil is a way to have some kind of a reference point, for each element that was tested for. Whereas what a random assortment of other gardeners in some instances thousands of miles away happens to think they need to do may have little specific applicability to your own situation.

Ok so I was thinking folks would mention things like they use 1 lb. of time release 10-10-10 one time in the spring for each year of tree age up to a max of 5lbs., along with 5-1-1 fish emulsion and liquid kelp via foliar feeding at a rate of one ounce each per gallon monthly during the growing season ... or we use Osmocote every couple moths to ensure a steady feeding and to keep trace minerals present ... or we just use a 3" layer of aged manure and compost for our established trees then cover it with 4 inches of arbor mulch ... or we add a cup of gypsum per tree every year to keep calcium levels up and we prefer this over bone meal because it does not alter the ph ... or we use miracle grow monthly, 1 gallon per tree ... or we always add bat guano that is high in phosphorus and we find that our fruit is larger and more plentiful than using other sources, etc... There are general guidelines and best practices for ongoing maintenance of fruit trees given we all know they use nutrients ... which are a finite resource in the native soil surrounding a tree ... and the way folks do this is often scientific ... but more often subjective and anecdotal with varying strategies and results ... interested to hear discussion surrounding this.

LOL!! I each classes on fertilization so no need to lecture me, thank you very much!! btw, everything I wrote is supported by horticultural science and is well and thoroughly documented if one bothers to research it so any "flaws" are in your eyes only. Everything growing consumes nutrients but seldom in concentrations that they need to be replaced annually - fruit trees are no different. The possible exception is N but that is easily replaced via an organic mulch. And you also seem to be under some delusions about what a dwarfing rootstock is. They only have limitations regarding topgrowth.....they are quite able to expand their root system to meet their nutrient needs, as are any other trees. The comparison of them to a container planting is invalid - 2 entirely different set of circumstance with NO relationship to each other.

But since you asked.........I use no commercial fertilizers on anything planted in the ground, including fruit trees. There is just no need to. But I do mulch annually with compost.

Fertilizer and fertilizing is probably one of the most misunderstood and most abused gardening practice. The above posts are a clear indication of that.

Well gardengal, since you "each classes on fertilization", I'll just bow down now and begin to recite "I'm not worthy". I have had many incompetent teachers throughout my scholastic career that thought they were right, but just pumped out bad info ... not saying that pertains to you though. I must confess, I appreciated your explanation of photosynth-asomethin', I was always wondering how that pesky chlo-fyll stuff got up into my darn leaves ... now I know.

Ok, back to being serious, thank you for the input. My experience has shown that timely and measured use of both organic and traditional fertilizers along with trace mineral sources has improved overall plant health and fruit quality as compared to no supplementation. Organic mulch does go a long way to filling the need to keep trees happy from many perspectives ... but telling folks to add "organic mulch" to correct a nitrogen deficiency is bum-scoop teach' ... that wide sweeping statement would include the addition of wood chips as a mulch, for example ... and that is a great way to deplete nitrogen from the soil in the short to mid term ... certainly isn't going to bump up nitrogen levels any time soon. This is why we add greens and browns to compost ... browns for carbon, greens for nitrogen to add the fuel to break it down. Last I checked, wood chips are brown, especially where our dog visits.

Hey gardengal, above you posted this to me... "And you also seem to be under some delusions about what a dwarfing rootstock is. They only have limitations regarding topgrowth.....they are quite able to expand their root system to meet their nutrient needs, as are any other trees."

I think you need to go through that lesson plan of yours and fact check that course you are teaching, see below ...

" The nature of size-controlling, dwarf rootstocks’ roots
is different from that of full-size trees. They tend to be
brittle, constantly breaking off at the feeding tips. They
are narrower in diameter (and thus have less conductive
tissues) and most notably are less efficient at taking up
and transporting water and nutrients to the top part of
the tree. These factors, coupled with the roots’ limited
extent and thus ability to explore and forage for nutrients
and water, contribute to the dwarfing effect."

https://casfs.ucsc.edu/documents/for-the-fruit-grower/rootstock-basics.pdf

As mentioned above this is a very individual thing, in my case I have performed soil sample analysis through the state university (LSU Soil Testing Lab). My soil is a fine sandy loam soil and is very deficient across the board (showing low to very low in all of the primary and most of the secondary nutrients) with about 1.8-2% organic matter, and a pH of about 5.8 (my personal testing showed 5.7) the numbers on the nutrients as exactly what mine are don't matter when it comes to yours, but for those that are wondering P 8.2 K 28.5 Ca 307.2 Mg 34.5 Na 6.7 S 6.7 Cu 0.33 Zn 1.13.

As to what I do, it depends on the type of fruit and time of year,

For my citrus, stone fruit and pear trees I use a commercial fruit / nut tree blend developed for local pecan orchards, 50 pound sack was about $12 from the local fertilizer blending plant It is an 18-9-11 Ammoniacal Nitrogen blend with micros, with a suggested application rate of 2 lbs per inch of trunk diameter for pecans, it does not have Mg, so I add Epsom Salts to my fertilizer schedule. For my blueberries I am currently using Epsoma Holly Tone organic fertilize, supplemented with 21-0-0 polymer coated slow release Ammonia Sulphate in the early spring. My thornless blackberries usually get a straight 8-8-8 commercial fertilizer ($9 for 50 sack), the same goes for my Figs, which only get light fertilization in the spring. Generally fertilizer is applied every 4-6 weeks Feb-June.

Gave your post a thumbs up ... dare I say "I liked Ike" ... anyways, that was very interesting for me to read. I'm curious how you administer the epsom salts ... foliar, root drench mixed in a watering can, mixed in with your fertilizer, etc... ? On the 18-9-11 blend for the citrus, stone fruit and pears, are you applying the 2lbs. per inch of trunk as suggested ?

I sprinkle the epsom salt along with fertilizer, and try not to over do it, knowing it gets washed out rather quickly I do this a couple of times per year. As to the application rate, it depends on type of fruit tree. I am bit paranoid on giving citrus too much Nitrogen as it can limit fruit development, the rest I tend to approximate, for home fruit growing I don't worry about optimizing performance like a commercial grower has to.

The reason I asked about the epsom salts is that I also use them on various things ... I read a piece that concluded that the magnesium is taken up much more efficiently via foilar feeding ... so I do that when correcting a visible deficiency ... but usually just throw a couple tbspns in a watering can and soil drench for routine feeding.

On the granular fertilizer you are using ... your concern is why I was asking how much you use ... because that does seem like alot of nitrogen if following the suggested usage ... don't want a ton of vegetative growth, I like fruit better than branches and leaves.

My apples, pears, and peaches all get 2-3 lbs of 10-10-10 time release and a handful of Osmocote Plus around Feb then a 4-6 inch layer of arbor mulch and that's it until fruit starts forming, then water soluble Maxsea 3-20-20 a couple times at 2 gallons per tree per application. Like you, figs a much lighter version of the same. My citrus are young so I push them pretty hard with 10-10-10 and a 2 gallon Miracid drench at least monthly. Persimmons don't like nitrogen much ... they reward you with dropping fruit if you over do it ... so I use a light 5-10-10 time release once in the spring.

Where I live soil temperature is often likely a limiting factor on Citrus growth. See http://www.crec.ifas.ufl.edu/extension/trade_journals/2011/2011_Nov_root_temp.pdf  My soil temperature here in western Louisiana as of yesterday was 67F which as you can see in the above link is still way below optimal for growth.