Cheapest way to add Ca, Mg?

[JustPotteringAbout]

I'm on a pH 5.5 - 6 soil (podzol) with granitic bedrock. Consequently the parent material doesn't impart anything in the way of minerals. The water is soft and has only 9.63 m mg.L^-1 of Caand 1.35mg.L^-1 ofMg

I have liquid Cal Mag for greenhouse plants but it's hella expensive to use as a soil ameliorant.

Whats the cheapest way to add Calcium and magnesium to the soil for ericaceous beds? eg soft fruits.
Whats the cheapest way to add Calcium and magnesium to the soil for non-ericaceous beds? eg Brassicas.

[Snadger]

I use magnesium limestone (dolomite) on my plot. It makes the plot a bit more alkaline but doesn't cause scab on potatoes.

The cheapest way would be to add wood ash.

[Thelma Sanders]

Calcified seaweed sounds like it'll do the trick "provides a rich source of calcium and magnesium "

[JustPotteringAbout]

Thanks. I'll try that for sure on brassicas and sparingly on the fruit.

[planetologist]

And be sure to grow blueberries without soil amendment.

[4Shoes]

Aye a bit of lime is needed to release more of the nutrients, and not knowing what Dolomitic lime did, found this summary on activity.

The primary difference between Agricultural Lime and Dolomitic Lime is that, in addition to containing calcium carbonate, dolomitic lime also contains a mixture of magnesium carbonate. Typically, the mineral is comprised of approximately 50% calcium carbonate and 40% magnesium carbonate with the remainder being other materials.

Reference
https://www.braenstone.com/2017/04/a...dolomite-lime/

if Acidity was the main problem to be addressed, it indicates that Agricultural Lime will bring the acidic level down faster (because in general it is finer powder).

Other article indicated £ for £ dolomitic lime is better value

[More basil]

Epsom salt for magnesium. Though you may get funny looks (as I did when I needed some in a hurry) if you buy it in large quantities in a chemist as it is used against constipation. Cheap to buy on-line and does seem to perk up plants. https://www.epsomsaltcouncil.org/use...its/gardening/