Severe calcium deficiency in mango seedlings

[mangoba]

How would you treat an extremely severe calcium deficiency in 2-3 years old mango seedlings that look like 6 months old please?

I added 40gr (almost 3 Tbsp) of calcium nitrate to each one's roots (diluted in irrigation water) and I also have been spraying a lower dose of the same product for the last 3 days. I do see progress but I'm too worried that I might not be doing enough. Sandy soil with >8 pH and low Mg content. I have been spraying Mg before and I gave Mg sulfate about a month ago. Let me know if I should be doing more, or less please...

Thanks!

[shpaz]

Are you sure they have a calcium deficiency? Calcium in not mobile in plants so spraying is not the ultimate answer. You said you already added calcium to the soil in a liquid form, I'd just observe them for a few weeks and go from there.

A tip, sandy soils don't hold into nutrients so work on increasing your organic matter, and use slow release fertilizers.

I have a clay soil that is rich in calcium so take what I said with a grain of salt (my PH is similar to yours though).

[mangoba]

That's an excellent point, when I sprayed I tried to focus on the new growth but I'm afraid the nitrogen might have burned the tender leaves. I had read that some plants may be able to move calcium, but I was very desperate to resolve the deficiency. I'm quite confident that it's a calcium deficiency, my soil also has plenty, overusing fertilizers and watering apparently washed it away in the seedling area!

[shpaz]

Maybe you should post a photo

[lebmung]

Add gypsum and use epsom salt. Bring down your soil pH. Probably your rootstock is Gomera type, which can take some salts well but your pH is still high.
Why would you spray calcium nitrate of course will burn all new leaves.