Leaves of young Mango tree are getting yellow

Question

I have a question about a mango tree that I've planted few months ago. At first, it was planted incorrectly and too deep so it took a bit more time than it should to sprout and get to sunlight. Since then, however, it was growing quite fast and nicely, until recently the upper leaves started getting yellow and a little bit curly. Older leaves that you can see on the right look much better, helthier and more green. But it's still not the ideal colour, I think. I'd like to know whether this is insufficient amount of water, or the soil is not suitable. However, for two months it had no problems and looked fine in the same soil.

And yes, it's in a bucket, which is not the best way to grow a mango, but there is no risk I think. It has holes on the bottom so the excess water flows out and I hide it if it's raining too much so it does not overflow fron top. The bucket, was colored white from inside, but these are used for carrying milk and such, so in no way it is toxic for humans, but for a mango tree? I do not know. But I will move him into an actual, bigger pot soon.

I am from Slovak Republic, living in a valley. Temperatures reach as much as 37C in shade, much more in the sun. Nights are not that cold, very rarely dropping under 15C. (Sorry for mistakes, English is my second language)

Answer 1

For this size of plant that bucket is way too big. Not enough roots to keep sucking up the water that did not drain away.

Your plant is suffering from not being able to do photosynthesis. There aren't enough chemicals with which it needs to make its own food. This plant needs a balanced fertilizer. 3 numbers; N - P - K...Less is Best, More is Death and None is Dumb. My very own little ditty about fertilizer. I'd get Osmocote 14-14-14 and use half of their recommendations for amount and applications.

The other problem is I think you've used garden soil? I can see a few weeds popping up that would not be there had you used sterilized potting soil. All plants, without exception, that are planted in pots need potting soil, never garden soil. Never potting soil mixed with compost or sand or anything else. Never with potting soil that comes with fertilizer or water holding gel, sponge gimmicks.

When growing plants in pots, you always start with the proper size for the plant as it is NOW. A seed would be planted in a 1"X2" seed starter with potting soil. Sterilized potting soil. Even then, that little bit of soil holds too much water and seeds will damp off. I use a spray bottle to germinate seeds.

A baby plant growing in that 1"X2" section, when the roots show out of the drainage hole, needs to be up potted into a 3"X3" little pot with potting soil only. Now is the time fertilizer should be added. Just a little.

When roots begin to show out of the drainage holes, that plant needs up potted to a one gallon pot; 6" diameter pot. I'd add a tiny bit of fertilizer at this step as well.

For your mango tree, the same process is necessary. Are you planning to plant this guy in your yard some day? If so, this plant will need to be acclimated to be able to handle full sun. Takes a minimum of 2 weeks for acclimation.

Lift your potted plant. Feel the heft. You'll be able to easily tell if that plant needs water. It will be heavy when it has plenty of water. Until that pot, soil and plant when lifted feels light, that is when you need to water and not before. The difference is very very obvious.

Hope this helps. Fertilizer, potting soil, smaller pot for the size of the plant and roots, water only when the pot feels light. The best place for this little tree is on a covered porch with absolutely no chance of temps going below 60 degrees Fahrenheit. Sounds like your summer?