Gini
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Epsom salt and fertilizer

I will transplant my tomato plants this weekend.
I was told to use epsom salt to fertilize.How do I use that?straight in the ground or mixed with water?
If I am planning to use the Miracle Gro tomato fertlilizer,.Is it ok to use both?
In any case,,How often and how much do I use?
During growing season I keep fertilizing how?
I am SUCH a beginner at this,,sorry...
:oops: ,
Gini

opabinia51
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Hi Gini,

I must say that I have never heard of using epsom salts as a fertilizer. The effect would be similar to using a salt based fertilzer being that water soluble nutrients would be immediately available to the tomatoe plants, the salts would also kill any beneficial soil microbes and they would not replenish any nutrients taken from the soil by the plant.

A better fertilizer to use would be a liquid fish or a liquid seaweed fertiler. Both of these are organic and not water soluble. Therefore, to release the nutrients that it needs, the plant will secrete small amounts of either acid or base to relinquish the chemical bonds that hold the nutrients to the soil.

Anyway, the point is that with organic fertilizers; you feed the soil and not the plant. This way, beneficial bacteria, fungi and whatever else is living in your soil will ward off any pathogens and also aid in feeding the plants.

Basically, I'm advising you not to use epsom salts or any salt based, synthetic fertilizers.

Kelp meal is a slow release organic fertilizer that tomatoes also love. All you need to do with this one is: add a handful into the hole that you place the plants into and then forget about it. (I also fertilize with liquid fish fertilizer each week but, you don't need to.)

For next year, start a compost pile up and use that as free fertilizer for you plants.

Newt
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Gini, I agree with Opabinia. You would do better to use organic fertilizers. I have heard of using epsom salt on roses to help them 'green up' but I wouldn't use it on veggies. Here's the Epsom salt Council site that explains what it's supposed to do.
https://www.epsomsaltcouncil.org/garden_benefits.htm

Newt

Durgan
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Epson salts, magnesium sulfate, has been espoused for years as a inducive to make strong healthy tomato plants. I tried to chase the story down last year and could find abslutely no evidence in a controlled experiment to warrant its use.

I tried it by mixing a teaspoonful of epson salts with soil around the root of the tomato plants last year on about ten plants. All the plants thrived so a result one way or the other was not even indicated.

I'm don't think placebos work with plants, so until a controlled experiment indicates usage I will pass.

Durgan.

aqh88
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One thing to remember epsom salt does not actually contain any sodium(salt). It is all magnesium sulfate. In fact it's even used in fish tanks as a fertilizer for aquatic plants or to increase the dissolved minerals in the tank because it contains no sodium, harmful salts, or excess fertilizers that might cause algae to grow. Whether sudden doses of magnesium is actually useful to tomato plants I don't know but I do see epsom salt sold for fertilizer all the time.

opabinia51
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Just a little chemical nomenclature correction here; sodium is not salt per se. Sodium metal is sodium as an element and sodium chloride is a salt. But, Magnesium chloride and a host of other salts are out there as well. A salt is merely the product of reacting an acid with a base.

Magnesium Sulphate is also a salt that is the product of reacting a Base like Magnesium Hydroxide with Sulphuric Acid. And therefore Epsom Salts are by nature salts and water soluble. And adding salt based fertilizers to soil provide an immediate substrate for plants to take up and use as fertilizer but, leaves nothing behind for plants to use in the future. So, the plants are left needing the grower to supply them with nutrients.

Furthermore, adding high concentrations of salts to soils kills beneficial soil organisms that fight off disease, decompose soil elements that will end up feeding the plants and a host of other properties and tasks.

Therefore, even though adding epsom salts and synthetic fertilizers may give you a so called healthy spurt of growth, in the long run they are detrimental to the soil and to the plants.

A huge problem in the world right now is all the synthetic and water soluble fertilizers that are used and that simply runoff into rivers and out into oceans.

The result is called Eutrophication and this results in what are termed dead zones where algae has taken over and killed every living organism for miles and miles. It become so bad, that not even the algae can grow.

Compost, some manure, good soil, organic fertilizers and so on will result in much healthier, disease resistant plants that produce lovely fruit that is so much more flavourful than fruit grown with synthetic fertilizers.

Midnight Smoker
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I have used epson salt in the amount of 1tbs per 2 gallons for magnesium defficiencies in the past with great sucess but there really is no need for it!!!

As long as your medium is good, and plants are healthy and disease free, you shouldn't have any problems.

Use liquid fish and seaweed mixed with water and also bat guanos.
Both of these are available in many different NPK ratios.

I'm also a big fan of a product called CHI. It's available from most hydroponic gardening stores and is used as a foilar spray.
It's made from the shell of crustacions(sp?) and helps plants deal with stress from a number of different sources by beefing up the plants cell walls.

You can also use crab shell in the soil as well.

Check out https://www.wormsway.com/


This is all I have used for the last 5 years and I will never use anything else...miracle-who :?:

The liquid seaweed as a foilar spay is as goos as it gets, and you can use it on prettymuch everything in the garden

Good luck and happy gardening :D

hugh
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The advice is correct. Only use epsom salts if you have a magnesium deficiency. This is a yellowing of the leaves that then becomes brown, then the leaves eventually fall off.

It is not that common. If you are planting outside and use a good balanced fertiliser, you should avoid it. I have only suffered from it in green houses, you know all that serilised soil and artifical environment - and then infrequently.

My advicce is if you are suffering from magnesium deficinency treat it - other wise leave alone, as you can build up residues.

Hugh

Danny
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Gini,

You've probably transplanted those tomato plants months ago, but may still wish to know more about Epsom Salts (magnesium sulfate) and how it is used in horticulture.

Magnesium is an element found only in compounds naturally, meaning it does not occur free in nature. "It is an essential element in human nutrition; it is the cofactor ... in clorophyll." "[Clorophyll is] any member of one of the most important classes of pigment molecules involved in photosynthesis." Source of qoutes is Britannica Concise Encyclopedia.

Magnesium is essential to photosynthesis. Plants do need it, though it is not always necessary to add it as a soil amendment. The soil may simply already have an adequate supply. Acidic soils are soils more likely to have inadequate levels. Epsom Salts can be added in cases where it is desireable to leave the pH at a lower level (acidic), for plants which thrive in pH levels below 7. Tomatoes grow best in levels between 5.5 and 7.5.

Magnesium is known as one of the lesser elements in fertilizers because much less by percentage is needed than the common elements. Many basic fertilizers do not provide it, though the better ones do, and list it along with iron, calcium, sulfur...

You can find a good leaflet online concerning its use at www.nes.ncsu.edu/depts/hort/hil/hil-551.html

Follow the recommedations in that leaflet and you won't do wrong. Magnesium does indeed make for stronger plants and does not cause harmful effects to soil when applied properly.

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tomakers
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opabinia51 wrote:Compost, some manure, good soil, organic fertilizers and so on will result in much healthier, disease resistant plants that produce lovely fruit that is so much more flavourful than fruit grown with synthetic fertilizers.
I'd like to see a study that shows this otherwise it is just opinion. I am no enemy of organic gardening, but I can't tell the difference between fruit from an organicly grown plant and one that has been fed with synthetic fertilizer and I doubt you can either.

MaggieMD
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Well, I am absolutely not qualified to enter the debate on Chemical nomenclature... however, a landscaper friend told me that using Miracle Grow for too long can harm the plant due to the "high salt content.' Also, I sent a query to the extension center about my squash plants and they suggested Miracle Grow can burn the leaves, so I am done with it. I was using it because it was easy to disperse as liquid -- I plant my tomatoes and other plants through landscape fabric, so feeding them means either a foliar spray or something pour able around the roots.

I got some fish "emulsion" now and I'm wondering if this is the same organic fertilizer many of you recommend. Have you used it as a foliar spray, or dissolved it in water and poured it at the base of the plants? Also, I have used kelp in a previous garden -- should I use that in addition to the fish emulsion or would that be overkill?

opabinia51
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Generally speaking when people refer to miracle grow they are referring to synthetic fertilzers which are by nature salts. Salts can burn plants by adding to much soluble plant food to the soil at one time.

Miracle grow also sells compost now but, I like to try to support local businesses and if I do buy compost or other organic fertilizers (I don't use synthetic fertilizers as they break down soil structure and kill beneficial soil flora and fauna) I like to buy locally made or grown products to support local businesses.

I'm lucky because there are some places near my home that sell bags of compost (I've recently moved to a new home and my compost pile is not yet producing and my sheet composting is just getting under way). But, look around your local farm communities and farmers markets because you'll be amazed what you find and it is usually cheaper to. :wink:

And you'll start to get to know your neighbours and start to establish community as well.

MaggieMD
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Thanks for the tip -- I can get compost and I already had my husband and son till it in to my garden before planting -- they used 300 lbs of compost in a 2,000 sq ft garden. But I can't fertilze with it now, since I covered it with landscape fabric and planted the plants through that fabric. I have to fertilize with something that is water soluable. I did put some fish emulsion on it and the plants seem to like it. But has anyone ever used it as a foliar spray? And any info on kelp would be appreciated...

hsharmon
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tomakers wrote:
opabinia51 wrote:Compost, some manure, good soil, organic fertilizers and so on will result in much healthier, disease resistant plants that produce lovely fruit that is so much more flavourful than fruit grown with synthetic fertilizers.
I'd like to see a study that shows this otherwise it is just opinion. I am no enemy of organic gardening, but I can't tell the difference between fruit from an organicly grown plant and one that has been fed with synthetic fertilizer and I doubt you can either.
I'm new here, but I'd like to share my experience with synthetic fertilizers. You might be correct that you could not taste the difference between synthetic and organically fertilized produce, I've never had the opportunity to do a controlled test.

However I have found that when I used synthetic fertilizers once I had to continue to use them regularly because the plants would turn yellow and sickly after the fertilizer washed out of the soil. However with organic fertilizer it stays in the soil and doesn't deplete it like the synthetics. Organic fertilizers or compost actuallly enrich the soil making it healthier and becoming part of it while slowly releasing nutrition to the plant over time.

You might see a short term growth spurt with a synthetic fertilizer but it is short lived and the effect wears off leaving you with depleted soil and a dependancy on chemical fertilizer.

I'm just saying that it seems more efficient and healthier for the environment to use something that's not harming our ecosystem and is more beneficial to the plant and your pocket book. :wink:

elevenplants
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I'd like to see a study that shows this otherwise it is just opinion. I am no enemy of organic gardening, but I can't tell the difference between fruit from an organicly grown plant and one that has been fed with synthetic fertilizer and I doubt you can either.
Organic gardening is practiced not solely for the improvement in quality and flavor of the harvest, but also because it is best for the enviornment. It doesn't take much to figure out that natural substances are better than man-made chemicals when it comes to what we put on the plants we end up eating...and putting into our compost, etc. Compost, manure, organic fertilizers are all natural by-products and as such, are prized for their value to our food sources. A little internet research about this subject will doubtless convince you also. :)

Rebecca

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Gary350
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Tomato plants need, nitrogen, phosphate, potash, lime. I use 15/15/15 fertilizer, ammonium nitrate and lime on my tomatoes. I usually get a bushel basket of tomatoes from each plant for the whole growing season.

If you are determined to use only organic fertilizer this is what you need to do. Mix 1 part wood ash, 1 part dirt, 1 part dry organic material in a 1 gallon container. Keep it next to your toilet. Every time you have to pee do it in the container. Bacteria is very quick to turn the Urine into ammonia and that is rich in nitrogen. The wood ash contains potash and lime. Urine is an excellent source of Phosphorous, Potassium, and other trace elements. And it is free. It only takes a week to make a 1 gallon batch of fertilizer. After 1 week use 1/2 of it for fertilizer. Mix the other half with another 1/2 gallon of wood ash, dirt, orgainic material and continue to pee in it for 2 days. The bacteria is already growing from the first 1/2 gallon so you use that as a bacteria starter it gets the next batch going very quick. You can harvest a 1/2 gallon of fertilizer every 2 days just keep adding more mix and keep peeing in it.
Last edited by Gary350 on Fri May 08, 2009 11:31 pm, edited 2 times in total.

Brandywinegirl
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I used Epson Salt last year and many of the plants died out of the blue. I guess I overdid it, or Epsom Salt is ust not good for the garden veggies.

I am going with compost, manure and topsoil this year!
:D

Haesuse
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another fantastic alternative is aquarium water. plants LOVE the nasty water that comes out of a fish tank.

damethod
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Gary350 wrote:If you are determined to use only organic fertilizer this is what you need to do. Mix 1 part wood ash, 1 part dirt, 1 part dry organic material in a 1 gallon container. Keep it next to your toilet. Every time you have to pee do it in the container.
LOL I'm sorry, but I almost puked upon reading!

myron26155
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Mix 2 tablespoons in a 1 gallon sprayer and foliar feed them. It's amazing!

myron26155
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Haesuse wrote:another fantastic alternative is aquarium water. plants LOVE the nasty water that comes out of a fish tank.
You are so right! Instead of dumping the old aquarium water down the drain I started pouring it around my Sago palm and it has been growing like crazy.

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freedhardwoods
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elevenplants wrote:Compost, manure, organic fertilizers are all natural by-products and as such, are prized for their value to our food sources. A little internet research about this subject will doubtless convince you also. :)

Rebecca
I too have nothing against organic methods when they are practical. Those things that you mentioned are "prized" by hardcore organic gardeners, which is fine. I will use those things when it is convenient, but I won't go out of my way to get it. When I think one of my gardens need organic matter, I have a dumptruck load of poplar (low acid) sawdust delivered in the spring and spread it several inches deep on top and then till it in. Before the last pass I spread a heavy dose of urea to help the sawdust decompose. I will till it about once a month until winter and by the next spring it will be ready to grow vegetables again. 8)

Jerseygardengirl
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This is an interesting thread. I've always heard that spraying a very small dose of epsom salt mixed in with a gallon of water helped fruit set, when sprayed on the blooms. Is this not true?

LOL at the pee suggestion. That's just funny stuff. :lol:

myron26155
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Jerseygardengirl wrote:This is an interesting thread. I've always heard that spraying a very small dose of epsom salt mixed in with a gallon of water helped fruit set, when sprayed on the blooms. Is this not true?

LOL at the pee suggestion. That's just funny stuff. :lol:
I haven'theard that- it may very well be true though. When my plants start to lose that deep green color I spray them with epsom salt and within a day they develop this beautiful dark green color that almost makes them look like fake plants. It doesn't last but a week or two but for a quick fix it's perfect.

jerrydietztx
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opabinia51 wrote:Hi Gini,

HI GUYS.. I DO NOT AGREE.. EPSON SALTS IS A MINERAL. HYDRATED
MAGNESIUM SULFATE. OR MAGNESIUM AND SULPHER, ALL PLANTS REQUIRE A CERTAIN DEGREE OF MAGNISIUM FOR REAL GOOD STEM
DEVELOPMENT ABD OF COURSE THE SULPHER ADDS SOME ACIDITY
WHIICH TOMATOES LIKE. CHECK THE PH REQUIREMENT AND U WIL
SEE. ALSO EPSOM SALTS IS VERY GOOD ALSO FOR ROSE GROWERS.
WIL GET MORE CANES,STRONGER STEMS AND MORE FLOWERS.
I SAY USE A SPOON FULL AT PLANTING TIME, WHEN YELLOW FLOWERS
APPEAR, ADD A SPOON FULL TO A GAL OF WATER AND SPRAY THE
FOLIAGE.
JERRY DIETZ
AUSTIN TEXAS

I must say that I have never heard of using epsom salts as a fertilizer. The effect would be similar to using a salt based fertilzer being that water soluble nutrients would be immediately available to the tomatoe plants, the salts would also kill any beneficial soil microbes and they would not replenish any nutrients taken from the soil by the plant.

A better fertilizer to use would be a liquid fish or a liquid seaweed fertiler. Both of these are organic and not water soluble. Therefore, to release the nutrients that it needs, the plant will secrete small amounts of either acid or base to relinquish the chemical bonds that hold the nutrients to the soil.

Anyway, the point is that with organic fertilizers; you feed the soil and not the plant. This way, beneficial bacteria, fungi and whatever else is living in your soil will ward off any pathogens and also aid in feeding the plants.

Basically, I'm advising you not to use epsom salts or any salt based, synthetic fertilizers.

Kelp meal is a slow release organic fertilizer that tomatoes also love. All you need to do with this one is: add a handful into the hole that you place the plants into and then forget about it. (I also fertilize with liquid fish fertilizer each week but, you don't need to.)

For next year, start a compost pile up and use that as free fertilizer for you plants.

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tn_veggie_gardner
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Ok, I can't help but reply to this one. As politely as possible, I would not want you to follow some advice given on here & be disappointed. Epsom salts would be a good additive if you are only using the MG fertilizer and nothing else, as it will provide necessary Mg for the plant. NPK is not all tomato plants need. They need calcium, Magnesium & a few other nutrients.

Regarding organic fertilizers, any master gardener, horticulturist, etc. will tell you that organic fertilizers will take time to break down in the soil & provide the nutrients they give, depending upon what's used. They are not bad, you just have to keep this in mind when using them. On the other hand, chemical fertilizers start prividing their nutrients almost immediately.

If you are using the standard MG Tomato food, I would reccomend using the Epsom Salts, dissolved into warm water, once every week or so. I would also reccomend some type of Calcium supplement. Please, if you feel like you have received opposing opinions on this, do your research & then pick whatever method you feel best, based upon the facts you find. Hope this helps.

- Steve

jerrydietztx
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tn_veggie_gardner wrote:Ok, I can't help but reply to this one. As politely as possible, I would not want you to follow some advice given on here & be disappointed. Epsom salts would be a good additive if you are only using the MG fertilizer and nothing else, as it will provide necessary Mg for the plant. NPK is not all tomato plants need. They need calcium, Magnesium & a few other nutrients.

Regarding organic fertilizers, any master gardener, horticulturist, etc. will tell you that organic fertilizers will take time to break down in the soil & provide the nutrients they give, depending upon what's used. They are not bad, you just have to keep this in mind when using them. On the other hand, chemical fertilizers start prividing their nutrients almost immediately.

If you are using the standard MG Tomato food, I would reccomend using the Epsom Salts, dissolved into warm water, once every week or so. I would also reccomend some type of Calcium supplement. Please, if you feel like you have received opposing opinions on this, do your research & then pick whatever method you feel best, based upon the facts you find. Hope this helps.

- Steve

Dazastar
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Contrary to the mistaken beliefs, Epsom salt is a safe "organic" fertilizer

https://factoidz.com/epsom-salt-goodies-in-gardening/

Cheers

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rainbowgardener
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Depends of course on your definition of organic and safe:

Most organic gardeners do not use epsom salts. They are a salt (chemically- not sodium, not table salt, but they are a salt -- technically , salts are ionic compounds which can result from the neutralization reaction of acids.)

"Epsom Salts' (technically Magnesium Sulfate, or MgSO4) is one of just a few water-soluble Sulfate minerals, and it is a soluble salt -- a salt that dissolves in water. ALL chemical fertilizers are also 'soluble salts'. When Ammonium, Potassium, Chloride or Nitrate dissolve in water, they are soluble salts. A little will fertilize the plants. Too much will damage and sometimes destroy a plant. That can happen quickly --or it can take time and build up slowly. THERE IS NO DIFFERENCE BETWEEN YOUR USE OF EPSOM SALTS AND THE USE OF A CHEMICAL FERTILIZER LIKE MIRACLE GRO. Because ALL chemical fertilizers ARE SALTS. Salts KILL microbes in your soil. I love my microbes. I love my soil foodweb. I love all the beneficials down in the dirt. One teaspoon of healthy soil holds MILLIONS of friendly microscopic organisms. If salt hurts my microbes, it's got to go." from https://en.allexperts.com/q/Fertilizer-717/EPSOM-SALT-HYDRANGEAS.htm

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applestar
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You know, I think the divergent thinking comes from the fact that people using non-organic methods in depleted soil supported by limited chemical fertilizers probably do see dramatic effects/benefits from using Epsom Salt, whereas organic gardeners who have been feeding their soil and using complete -- and I mean REALLY complete, not marketing hype -- fertility amendments like well-made compost probably don't see much of a difference, or even see decline in their plants due to the massive hit/imbalance created to what was a stable system.

Dazastar
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Many thanks for the correction. That's the last thing you want, a quick fix that destroys the long term benefits of essential organisms etc

Cheers again

TZ -OH6
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Doubling time of microbes can be a short at 30 minutes, so if you kill some of them with too concentrated an application of "salt" they will repopulate quickly after that concentration is diluted. Letting the soil dry out will also kill microbes, as will ultiviolet light shining on the soil. Those of us who use "Salt" fertilizer for composting wood chips know that, just like plants, microbes use those minerals too. Mineral fertilizers are also used for growing mushrooms.


Magnesium sulfate ---> sulfur is used in the linkages holding proteins/enzymes together in the proper shape for functioning...like bolts holding peices of machinery together. Magnesium is a part of many plant enzymes and enzyme cofactors so plants need it to function efficiently. Magnesium is also a part of the chlorphyll molecule. By the time the plant starts to show signs of magnesium deficiency (yellowing) in the chlorophyll complement the enzyme cofactor magnesium levels are already low, but magnesium is stockpiled in the cells vacuoles so one shot of epsomes salts will last the plant for quite a while.

Calcium is needed for strong stems (structural hardening during cell wall formation). Magnesium is not. Small plants don't need a lot of magnesium (and spring soil is high in nutrients so it is in relatively high concentrations early in the season) so adding epsoms salts to a planting hole, where it will leach away before the plant gets big enough to need it, is wasteful. Calcium, on the other hand is problematic early in the season (see the BER sticky thread) so adding that to the planting hole makes a bit more sense even though most of the active root tips will be far away from the hole in a week or two from planting.

Soils are generally not low in magnesium so unless you see problems there is no reason to dose with epsoms salts. If you have chronic problems, and soil tests show acid soil, dolomitic lime will provide a long term magnesium source.


Epsoms salts are unusual (as "fertilizer" salts) in that they can be applied in unusually high concentrations without harming the plants. Some commercial growers drench orchid pots with concentrations as high as 2 tablespoons per gallon of water. The reasonings for this is that it supposedly will help flush fertilizer buildup from the pots.


Textbooks (plant physiology, horticultural etc) generally skim over details, and possibly as a result much of the stuff on the web is 'fanciful' to put it nicely, but if you really want to know what your fertilizer "parts" do inside a plant I recommend this relatively expensive doorstop of a text book.

Marschner's Mineral Nutrition of Higher Plants, Second Edition (Special Publications of the Society for General Microbiology)

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applestar
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$103 at amazon! :shock:
I added it to my wishlist. :wink:

TZ -OH6
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Its a paper back too :roll:



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