Influence of soil nutrients on fruit flavor?

Depends on the expense Mark and what you would learn. Here a simple soils test is very inexpensive as compared to foliage analysis. I have the county test my soils for free and I bought a sampling test kit to do supplemental tests in key areas. I also purchased a soil testing meter that measures moisture, ph, and light levels.
I find these articles on CEC pretty informative about improving soil fertility. They would be applicable once you have soil test results.
Soil science and CEC articles

CEC benefits

Benefits of soil organisms: Soil Organism - an overview | ScienceDirect Topics

Do earthworms create humus?

Earthworms can eat their weight in organic matter and soil each day to create nutrient rich castings. Earthworms help create humus—a dark brown-black type of soil which holds important nutrients in place for plant growth and use.

How Does Humus Help Plants Live?

Municipal leaf waste nutrient components

Benefits of nitrogen fixing legumes, crimson clover best winter cover crop to plant in spring. Alfalfa, white and red clovers are perennials.

Nutrient availability influence of CEC:

How does Organic matter influence CEC of Soil?

It influences the soil’s ability to hold onto essential nutrients and provides a buffer against soil acidification. Soils with a higher clay fraction tend to have a higher CEC. Organic matter has a very high CEC. Sandy soils rely heavily on the high CEC of organic matter for the retention of nutrients in the topsoil.

What is humus and why is it important?

Humus is dark, organic material that forms in soil when plant and animal matter decays. … Humus contains many useful nutrients for healthy soil. One of the most important is nitrogen. Nitrogen is a key nutrient for most plants.

What is humus and how is this beneficial to plant growth?

It’s called humus when it has completely decomposed. It is the thick brown or black matter that remains after the decomposition is complete. Humus contains many nutrient minerals that improves the health and fertility of the soil. Carbon is critical for healthy soil conditions, and humus is roughly 60 percent carbon.

Humus allows soil organisms to feed and reproduce, and is often described as the “life-force” of the soil. The process that converts soil organic matter into humus feeds the population of microorganisms and other creatures in the soil, and thus maintains high and healthy levels of soil life.


only things i remember my father putting under his fruit trees was a light sprinkle of lime and epsom salts. after reading this i guess he knew what he was doing. my ph is about perfect for fruits so i put some gypsum and epsom salts in the spring. add sulfur to my blueberries but only every other year.


Ca and Mg are requirements for fruit production. Potash (K2O, symbolized by K on fertilizer packaging) is the primary driver of fruit quality. Note that excess potash can maim plants, so a soil test is recommended before purchase. Application to perennials is usually skewed towards the late summer and Fall (in milder climates) to provide resources to winter root processes. By skewed, I mean 2/3 to 3/4 of the potash is applied in the 2nd half of the season. Potash in the form of plant meals (e.g. alfalfa meal) is best applied before fall weather as it takes time to achieve solubility in the soil. Wood ash contains potash but is also 25% lime and is not recommended unless your soil is acidic. Potassium Sulfate is in the opposite category, introducing acidity to the soil so it is only recommended for alkaline conditions. For that situation, Sul-Po-Mag (0-0-22-22-11) is usually a better option as it also provides supplemental Mg. Muriate of Potash should never be used as it is actually a pool chemical containing serious amounts of chlorine.

Annual application amount rules of thumb:

  • For pit, pome, and citrus fruit, use a quantity equal in % by weight of annual Nitrogen inputs. Both manure and compost have about a 2% imbalance in N compared to K. So if you’re applying 10 lbs total per tree annually, you are looking for another 0.2 lbs of K which could be obtained with 0.9 lbs of Sul-Po-Mag (0.2 lbs / 22% = 0.9 lbs).
  • Cane berries, no more than half the annual % N input, which you might already be achieving with your current regimen.
  • Northern nut trees: Zinc is the most important supplement for quality in these crops. There are professional zinc supplement products for these crops and the application rates are given on the labels. For potash, the N /K balance is the same for pomes.

Also worth noting: the recommended annual Nitrogen input for maturing perennial fruit trees (e.g. pruned to 8 ft high x 10 ft wide) is net 1 lb – typically not to be applied all at once. For example: 20 lbs of a manure that supplies 5% N would meet this requirement, and if properly cured could safely be divided into 2 or more applications. In contrast, a water-soluble fertilizer supplying 20% N would only require 5 lbs/yr but due to the concentration should be split into at least 4 applications.


Yes I had assumed my soils here being from volcanic and glacial till would be acidic, but we noticed our blueberries are suffering badly this summer. So when I tested the ph it was always over 7, much too alkaline so I am now starting to add sulphur probably each year. Will only use gypsum where calcium is needed


Also insure that they receive no (or very little) nitrate nitrogen.



Yes we have brought this up and it’s true. Growing fruit right to reach maximum quality!

Things like bitterpit are caused by lack of calcium What causes bitterpit

@alan was bringing up calcium issues back on gardenweb which may have been where i learned from but i can’t recall now. It may have been from college. Here is one place where he discussed calcium

Briefly i discussed the basis of soil science here ReplytoOlpea-topic Harrow Program Pears - #144 by clarkinks . @marknmt there is much more we posted. Acres USA was some of my favorite reading material seems like over 20 years ago. Grace Gershuny and other authors were some of my favorites that covered basic soil science.

The pictures of my soil in my garden in this thread says plenty. The food tastes great from the garden. It is very healthy food!


It is rainfall and irrigation water that set the pH of the soil of cultivated plants – unless of course the planting is in a large deposit of a soluble acidic or alkaline mineral, e.g. the majority of FL.

Municipal water is purposely set at pH >= 7 to reduce corrosion in pipes. You can try battling this with acidic soil supplements. In the long run it is more effective to dose the water with acidification. Depending on your water pressure and water volume needs, Venturi injectors or Dosatron are good choices. The EasyFlow products are not recommended for any horticultural purpose.

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Good ideas Richard
I agree having been a public works director I am well aware of the ph of drinking water and pipe protection methods that cities employ. I need to do some more research to see if I can modify the ph of my water as I apply it


Is there an ideal pH for water, or does it vary depending on soil pH?

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Was this from Home Depot? As I understand the issue, gypsum does not improve the texture of most clay soils and is most widely useful in the west coast where sodic clay soils are common- the only types of clay that are improved by it.

I would suggest that nutrients affect fruit flavor mostly by way of deficiency and that in the east coast, by far, the most common deficiency is calcium. I seem to have gotten good results with only a couple of mid-summer calcium sprays this year on varieties highly susceptible to corking- I don’t want to have to do more apps than that so will stick to it as long as it works. A very light cropping Jonagold tree that I didn’t bother spraying got terrible corking, the only I saw this season.

The tendency of varieties to suffer calcium deficiency is highly variable and I don’t recall ever seeing it in heirloom varieties- maybe that had something to do with their selection as cultivars before growers every used foliar calcium

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It varies depending on crop.

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There will be people still not convinced that nutrients impact flavor. Next time your tree over produces and your fruit tastes blan think about what we said here again if your not convinced yet.


And no muriate of potash:)

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I would be very careful about using balanced fertilizers on Apple Trees - especially with regard to Honeycrisp, Enterprise, Freedom, Ida Red, etc. The second and third numbers affect the ability of the trees to utilize/uptake calcium and you will end up with bitter pit at a much higher rate. This is even true when applying calcium sprays during a spray schedule because they usually contain nitrogen anyway to facilitate uptake. I have spoken with many big time orchard operators - some of which do not even fertilize apple trees to avoid the problem and never use potassium.

I do think nutrients matter. Our apples and pears are very flavorful, especially our Honeycrisps, Pristines, Golden Delicious, Ginger Golds, Enterprises, Sundance, Winecrisp,Granny Smiths and Limbertwigs. Tom Burford used to recommend chicken liter - used by his father. My own soil is very nutrient rich, but for Boron (very typical of soils in Viginia and W. Virginia). Almost immediately adjacent to my orchard are my corn/soybean field where with an application rate of 3 tons of liter per acre we have no problem exceeding 200 B/acre with filed corn and hitting 60 B/acre with soybeans. My wife also successfully grows watermelons/cantaloupes/raspberries/blackberries within 50’ of the orchard and I do use heavy 10-10-10 on that or even 46-0-0.

Keep the potassium out of the orchard is what I would recommend unless your expert tree fruit extension agent tells you otherwise and those at the Alson Smith Center in Winchester are very careful about that.


just went around yesterday and scattered some gypsum and epsom salt under all my fruits. i do this every few years and it seems to help keeping the trees/ bushes healthy and the fruit looking/ tasting good. ive stopped putting manure under my fruit trees but still put some around the fruit bushes which are heavier feeders. they just get a few in. of green woodchips to discourage the weeds from growing.


This is probably an excellent idea in your locale but can have horrid results elsewhere.

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Usually it means that there are too few leaves to serve individual fruit and so less sugar and other flavorings are delivered to it. The second most important influencer to fruit quality is the amount of available water in the 2 or 3 weeks leading to ripening (at least that is when I believe soil water has most influence) and the amount of sun those leaves receive at that time- the 30 or so leaves closest to any given piece of fruit.

It is not common for nutrient deficiency to be an issue about fruit quality around here beyond the issue of calcium in corking susceptible apple varieties. I cannot speak for KS.

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I would go further to add that once susceptible varieties are established, do not apply wood mulch or leaf mulch, which is loaded with available K and leaches it into the soil rapidly. Unfortunately in my dry farming nursery I need that mulch and many of my orchard apple trees are adjacent to mulched nursery trees and I struggle with corking- especially on Honeycrisp and Jonagold. Calcium sprays do help.

My nursery trees are more valuable to me than my orchard trees so they get the preferential treatment.


The issue in my opinion is that since Kansas soil is mostly clay loam and its rich in unusable minerals that are locked up in clay. The way i unlock those minerals is by applying orgsnic matter like composted manure. The way cations and anions work is they are positively or negatively charged and the roots work the same. Im not trying to over complicate it but the cec cycle can only exchange nutrients available in a usable form. Literally without compost my tree can literally starve to death in nutrient rich clay it cant use. The water is an important part of the tree doing well and leaves are needed for photosynthesis just like you said to use the suns energy. If there are not enough leaves the tree does poorly. Calcium(2+) is a calcium cation. You know all this Alan so im saying this for others reading it to try to clarify soil science. .If i dont say this people think because clay test rich in calcium we are good to go but we are not at all good in that situation.


How does organic matter affect access to minerals in the clay beyond improving aeration? Obviously, the organic matter in itself is rich in available nutrients, some gradually and some immediately but the literature I’m aware of emphasizes its role in separating clay particles and leaving room for air. My only problem with clay is it drowns trees- the nutrient missing is oxygen.

As far as deep understanding of CEC, I plead ignorance beyond the bit about negative and positive ions.

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