What is wrong with my mango seedling

[DianaL]

Hello everyone,
Please I need help.
I have this little buddy, planted some time in March (don't know the exact date).
The leaves You see are from the first push and since then all the new growth just stopped and fell off (once it fell off and now it started pushing but has stopped again).
I definitely chose too big pots for them so I recently repotted them into smaller pots.
As for the care they were kept under plastic in order to adjust them to lower humidity slowly, now growing without it. When it's warm I place them outside, when inside I place them under grow lights. After it stopped growing I was trying to add some fertilizer (universal (4-2-3) or citrus (unknown but listed it's suitable for cactuses, citrus and bonsai) once in a month). As for the soil it's kept in what they call here soil for indoor plants mixed with lot of perlite to keep the drainage (previous soil had poor drainage that's also the reason I repotted them). The leaves were like this basically since the first month of the plant but now it began to deteriorate quickly.
In the pictures, you can see roots, leaves and the new growth.
I am desperate cuz I rly dunno what's wrong with it.
Could it be root rot? Or overwatering due to its big pot or maybe anthracnose? Or maybe overfertilizing? Maybe potassium or magnesium deficiency?
I would be truly happy for any advice as I have a few more seedlings on their way (germinating)!

[DianaL]

This is how it looks now. I changed soil and gave it some potassium. Any ideas? 🙈

[Jaboticaba45]

It looks like it is not getting enough light. Also imo growing tropical fruits inside is a big nono. Since it is summer, you might want to try to bring it outside in partial shade so it doesn't get burned.

Hello everyone,
Please I need help.
I have this little buddy, planted some time in March (don't know the exact date).
The leaves You see are from the first push and since then all the new growth just stopped and fell off (once it fell off and now it started pushing but has stopped again).
I definitely chose too big pots for them so I recently repotted them into smaller pots.
As for the care they were kept under plastic in order to adjust them to lower humidity slowly, now growing without it. When it's warm I place them outside, when inside I place them under grow lights. After it stopped growing I was trying to add some fertilizer (universal (4-2-3) or citrus (unknown but listed it's suitable for cactuses, citrus and bonsai) once in a month). As for the soil it's kept in what they call here soil for indoor plants mixed with lot of perlite to keep the drainage (previous soil had poor drainage that's also the reason I repotted them). The leaves were like this basically since the first month of the plant but now it began to deteriorate quickly.
In the pictures, you can see roots, leaves and the new growth.
I am desperate cuz I rly dunno what's wrong with it.
Could it be root rot? Or overwatering due to its big pot or maybe anthracnose? Or maybe overfertilizing? Maybe potassium or magnesium deficiency?
I would be truly happy for any advice as I have a few more seedlings on their way (germinating)!

Also you can't choose a pot that is "too big"
Hope that helps!

[DianaL]

Thank You very much for your response! I use led grow lights when there's not enough light. When warm I take them outside during the day. The problem is that we endure the coldest summer in last 20 yrs so the night temps can get as low as 10°C so I was afraid to leave it outside. Do you think it needs even more light that lamps and sun can provide in such conditions?
And I chose quite the huge pot bcs it was extremely wet below the root and it would most probably completely rot if left in there.

[brian]

My greenhoused grafted mango gets those same partial-brown leafs also sometimes.  I have always wondered why.  It seems very healthy otherwise and constantly puts out new growth and has flowered twice. 

Diana, Prague is at ~50 latitude, I am around 40 (much further south) and my mango is doing great in a full-sun greenhouse with no additional lighting.  It might be possible for you to grow a mango there if you keep it warm enough.  I don't know if anybody has ever done it before.

[DianaL]

I wouldn't mind if it continued to grow. However, the leaves you see are the first push that came from seed and since then all new growth stopped in the middle of process and fell off (green and not deformed, just small). I hope it gets better bcs I plan to graft them next year. I tipped the tops of both seedlings 2 weeks ago. The healthier one seems to be trying to push but this one does nothing (when I cut off the top it was green so not dead). Now I live in a rented house so there's no point in building a greenhouse. After I finish my studies I will move back to my hometown (Bratislava) where I plan to build my own house with enormous heated greenhouse for my tropical buddies. As for growing mangoes here I know of many people who do actually and have trees up to 20 yrs old. The problem is, though, that most people have trees grown from seeds so they don't fruit yet and probably never will.

[brian]

Very nice.  You can try to figure out how to keep yours alive, and when you are ready to settle down get a nice grafted variety