Oh oh, did I goof with Epsom Salts?

Old 12-04-01, 12:53 PM
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Oh oh, did I goof with Epsom Salts?

I had heard that epsom salts were not a fertilizer, but act like a tonic to plants.
So, even though it's the beginning of December, on a mild day last week, I sprinkled a bit of epsom salts around the base of recently transplanted fir and pine trees on my property. I figured the snow would add the magnesium through to the root zone as the ground thaws.
Then I heard somewhere that epsom salts are a FERTILIZER after all! Have I killed my new trees?
Old 12-04-01, 02:06 PM
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I seem to remember using it for rhododendrons and azleas, and something in the back of my mind says we may have used it when trying to change the bloom colour of hydrangeas (or that may be aluminum sulfate) - That was YEARS ago, though , and my memory isn't as clear as it used to be...

As you probably already know, magnesium is an essential micronutrient for plants - I believe it helps with the photosyntheseis process...

Here's a website that describes a bit about why epsom salts are used in agriculture (sorry - its a Commercial site, so it does have a Brand name in it...)


and another that describes the roles of many of the macro & micro nutrients


I think that as long as you didn't use an outrageous amount, your plants should be okay.

Old 12-04-01, 03:46 PM
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Oh oh...epsom salts

Thank you, howie, bet you heard my (cross-country) sigh of relief that I haven't killed 85+ trees.
The link "granite/hydro" is excellent and I've bookmarked it, thank you. I also learned that there's quite a connection between magnesium and calcium, and I'd have to dig in my files to see if the soil test showed calcium deficiency.

I used a small handful around the base of each tree.

I too recall (barely) from my residency on the Wet Coast (Vancouver) that epsom salts will change the color of hydrangea blooms...but I can't remember what is the opposite to change the color back the following years. Probably lime?

Enjoying your extended summer?
Old 12-06-01, 09:10 AM
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Hi Barb,

Just to add a bit...this site has a garden page of facts. Click on Fertilizing with Epsom Salt . I didn't take you right to the page since there are a lot of other interesting and informative articles.


I add 1/4 c. epsom salt to my roses every spring, but didn't know you could add it to trees. Learn something new every day!

Old 12-10-01, 06:55 AM
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Thanks, Gami, for the interesting link.
Wish I'd read earlier testers found diluting in water then spraying onto leaves to result in improved plant health...better than sprinkling epsom salts on ground or diluted in water and then watering soil with it.

Now I've gotta find my soil test (where did it go?) to see if I've got a calcium problem because of how that reacts with magnesium.
Scads of great stuff on that page.
Old 12-12-01, 03:14 PM
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You're welcome, Barb! Did you find your soil test kit?

Yep, lots of good info on that page!


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