epsom salts

t-ham · May 23, 2011

Good Morning All,

I've come across some refs lately to epsom salt's ability to assist nitrogen uptake. I'm curious as to whether this ability is substantial or negligible.

Could someone either give me the main points on the subject or point me to a relevant thread? Specifically is this something that should be done preplanting or is it done periodically during growth, or, is it only done when indications like chlorosis are observed? Additionally, I was always under the impression that generally speaking, "salt=bad for soil"(like the buildup on the surface of potted plants long overdue for repotting), so I'm sure there are some fairly specific rules as to amounts to be used.

Thanks in advance,

Tom

attml · May 23, 2011

I believe epson salts have become a hot issue of late due to this thread? http://tomatoville.com/showthread.php?t=18309 Carolyn has some beautiful plants and some really nice tomatoes!

fortyonenorth · May 23, 2011

I just posted this point on another thread, but I'll repeat it here: get a professional soil test to find out what you "have" in your soil. If you don't do this first, adding anything is folly. If you already have adequate Magnesium, adding more will be counterproductive. Based on soil type, organic matter and other factors, your soil can hold X amount of nutrients. If you you take up too much of "X" with Magnesium (or any other nutrient, for that matter) there will be inadequate room left for the others. The Calcium:Magnesium ratio, in particular, is critical. Only with a soil test will you be able to make an informed decision.

dice · May 24, 2011

Epsom salt is magnesium sulfate. The sulfur in it is needed for
nitrogen uptake, but most common garden topsoils have plenty
of sulfur. Sulfur is in many fertilizers in other forms, too
(potassium sulfate, ammonium sulfate, sul-po-mag, etc).
The magnesium in epsom salt is used by the plant in chlorophyll
production. Your soil may or may not have enough magnesium
(which is also part of dolomite lime).

If you are using epsom salt, recommended practice is to
side-dress it (put it in strips along the sides of the plants on top
of the soil), so the roots reach it before rain or irrigation water
washes it out of the soil. You can also dissolve a tablespoon of
it in a gallon of water and soil drench with it around the rootball
of a plant if your soil or container mix is deficient in magnesium.

You may find this document, "Magnesium Basics" from
Spectrum Analytic, useful in understanding what magnesium
does for your plants and the various factors that can
influence its availability to the plant:
http://www.spectrumanalytic.com/supp.../Mg_Basics.htm

May 23, 2011	#1
t-ham Tomatovillian™ Join Date: May 2011 Location: rockland county, ny, usa Posts: 36	epsom salts Good Morning All, I've come across some refs lately to epsom salt's ability to assist nitrogen uptake. I'm curious as to whether this ability is substantial or negligible. Could someone either give me the main points on the subject or point me to a relevant thread? Specifically is this something that should be done preplanting or is it done periodically during growth, or, is it only done when indications like chlorosis are observed? Additionally, I was always under the impression that generally speaking, "salt=bad for soil"(like the buildup on the surface of potted plants long overdue for repotting), so I'm sure there are some fairly specific rules as to amounts to be used. Thanks in advance, Tom

May 23, 2011	#3
fortyonenorth Tomatovillian™ Join Date: Jan 2010 Location: NW Indiana Posts: 1,150	I just posted this point on another thread, but I'll repeat it here: get a professional soil test to find out what you "have" in your soil. If you don't do this first, adding anything is folly. If you already have adequate Magnesium, adding more will be counterproductive. Based on soil type, organic matter and other factors, your soil can hold X amount of nutrients. If you you take up too much of "X" with Magnesium (or any other nutrient, for that matter) there will be inadequate room left for the others. The Calcium:Magnesium ratio, in particular, is critical. Only with a soil test will you be able to make an informed decision. Last edited by fortyonenorth; May 24, 2011 at 02:48 PM.

May 24, 2011	#4
dice Tomatovillian™ Join Date: Jan 2007 Location: PNW Posts: 4,743	Epsom salt is magnesium sulfate. The sulfur in it is needed for nitrogen uptake, but most common garden topsoils have plenty of sulfur. Sulfur is in many fertilizers in other forms, too (potassium sulfate, ammonium sulfate, sul-po-mag, etc). The magnesium in epsom salt is used by the plant in chlorophyll production. Your soil may or may not have enough magnesium (which is also part of dolomite lime). If you are using epsom salt, recommended practice is to side-dress it (put it in strips along the sides of the plants on top of the soil), so the roots reach it before rain or irrigation water washes it out of the soil. You can also dissolve a tablespoon of it in a gallon of water and soil drench with it around the rootball of a plant if your soil or container mix is deficient in magnesium. You may find this document, "Magnesium Basics" from Spectrum Analytic, useful in understanding what magnesium does for your plants and the various factors that can influence its availability to the plant: http://www.spectrumanalytic.com/supp.../Mg_Basics.htm __________________ -- alias Last edited by dice; May 24, 2011 at 02:49 PM.

May 23, 2011	#2
attml Tomatovillian™ Join Date: Jan 2011 Location: Annapolis, Maryland Posts: 222	I believe epson salts have become a hot issue of late due to this thread? http://tomatoville.com/showthread.php?t=18309 Carolyn has some beautiful plants and some really nice tomatoes!