Early maroc en exterior.Bogotá, Colombia

Los puntos en las hojas sugieren carencia de Calcio, sería bueno también, añadir algo de Magnesio.

The stem is just sunburnt. This isn't a problem. The yellow leaves suggest you need more nitrogen. Find a fertilizer with a high nitrogen ratio. The 3 numbers on the bottle represent N-P-K. You want a fertilizer with an N number higher or close to the other two. So 3-1-2 would be a good choice but 5-10-21 would be a bad choice because the other two nutrients are so much higher.

May also be root problems, a bad ph, a too high ppm, overwatering... so exclude these first before supplementing with all NPK.

Looks like NPK deficiency, N from the yellow leaves, P from the red branches and K from the leaves getting crispy, with the brozeish color and dying.