Have anyone tried. . . Epsom Salt with cacti ?

[Plantcelot]

Howdy!

I have read a lot of good things about Epsom salt for plants and I'm wondering if any of you have any experience with it with cactus.

I read that 1 tablespoon to a gallon of water is a good formula for potted plants.

I got the following from one of the web sites:

(This is straight from epsomsaltcouncil.org : "Studies show that magnesium and sulfur, two components of Epsom Salt may:
Help seeds germinate
Make plants grow bushier
Produce more flowers
Increase chlorophyll production
Improve phosphorus and nitrogen uptake
Deter pests, including slugs and voles")

If any of you use it how frequently do you use it?
Good experiences or bad experiences?

[phil_SK]

You do have to be careful adding single salts as whilst it might help increase magnesium uptake it can make it harder for the plant to take up other essential trace elements.
I should add I have no experience of using Epsom salts. Most commercial fertilisers contain sufficient trace elements, such as magnesium.

[Plantcelot]

That was fast, good input thanks

[iann]

Not in a pot. Asking for trouble as Phil says. A good fertiliser has enough magnesium certainly for any cactus. And if your soil chemistry was so out of whack that you needed to dose with a single nutrient then you really should replace the soil.

I've used it in the garden. I have a highly calcareous soil and put added epsom salts on heavy feeding plants. Magnesium tends to be deficient in some calcaerous soils (although not all) and that can prevent the plant taking up other nutrients. It is also difficult to "overdose" in a garden bed. I buy it as magnesium sulphate from the agricultural store for about a tenth the price of "branded" epsom salts.

Beware the advice of marketing boards, they only ever give you half the story. Like the Miracle Gro advert "up to twice as big" as if you grew it in a soil-less medium with no nutrients at all, but not twice as big as if you grow it in a good soil or with any other fertiliser

[Lachy]

Yep - I definitely agree on this. Adding a single trace element (other than one of the big three of Nitrogen, Potassium or Phosphorus) is usually not necessary. Most complete plant foods - indeed, tomato food seems to be the benchmark - will provide the correct balance of trace elements without adding any boosters.

[GeneS]

There is a product by Sumitomo Corp called MagAmp. It is a granular, slow release 17-40-6 with 15% Magnesium added plus other traces. I know of it's use by some commercial growers with great success. I've never personally given it a thorough test but think that it has great potential for greenhouse use on seedlings through young plants. Like many of these products, pH control becomes a large part of the success recipe.

GeneS

[Plantcelot]

Great, thanks! All of that makes a lot of sense. I will look into the the MagAmp and the tomato food.