Dear Grand Master Grower âŠ..
Itâs called the Die-Back at this stage of the growth. It happens when the plant didnât get or got barely enough Nitrogen to support the stretch. The plant is now moving its Nitrogen, mostly from the bottom, to save the tops.
You must also know that adding Nitrogen is too late, the roots are processing only Potassium and Phosphorus at this stage now. The only way to add Nitrogen in this situation is a foliar spray with amino acids and some nitrogen. But I donât really recommend.
My best advice would be to let the dying leaves until theyâre ready to fall.