Where can you go to get your soil tested for magnesium?

Zoidy,
Not sure where you are located, but...

Check with your local/county extension service. They all do soil testings.

Generally the soil tests done at the County Extension offices just tell you the soil's pH and soluble salts content. If you want a more detailed test done, it costs much more - $25 last time I saw the kit. The Extension office has the kit for you to send your sample in, and it is tested at the nearest agricultural university lab.

But magnesium generally comes in an extremely soluble form, so if you're thinking of testing soil in a garden bed or pot you've been watering regularly, or if you've had a lot of rain it's likely you'll find there's little or no magnesium. Also it's very good for most plants and it's hard to imagine there ever being too much in soil. It's necessary for plants to produce chlorophyll in their leaves.

Your plants will probably tell you if they need magnesium, typically they will develop interveinal chlorosis, yellowing leaves with green veins, usually on the oldest leaves. If it's on the youngest leaves it is more likely to be iron or manganese deficiency. There are some pictures here:

https://www.google.ca/search?q...

Are you seeing something that suggests a problem? The cost of soil testing varies widely, some labs charge a lot as Elaine said, others are much less.

dyzzypyxxy said:
But magnesium generally comes in an extremely soluble form, so if you're thinking of testing soil in a garden bed or pot you've been watering regularly, or if you've had a lot of rain it's likely you'll find there's little or no magnesium. Also it's very good for most plants and it's hard to imagine there ever being too much in soil. It's necessary for plants to produce chlorophyll in their leaves.

I agree! Magnesium is extremely necessary for chlorophyll. And magnesium does leach out of soil. I have found that sprinkling Epsom Salts (contains magnesium and sulfur) onto the soil and watering in thoroughly every 3 months or so will greatly benefit plants. And it's cheap...a few tablespoons will go a long way!