Magnesium Deficiency

Magnesium deficiency is a nutrient disorder that appears during cannabis cultivation when plants lack sufficient bioavailable magnesium. Visual symptoms typically manifest first in older foliage as interveinal chlorosis—yellowing between leaf veins while veins remain green—often progressing up the plant. The condition occurs in hydroponic, soil, and coco systems, commonly triggered by pH imbalances, excessive potassium or calcium competition, or insufficiently buffered growing media. Magnesium is essential for chlorophyll synthesis and enzyme activation, making early identification critical for yield protection. Correction typically involves foliar applications or root-zone adjustment depending on growth stage and medium type.

Breeders rarely select directly for magnesium deficiency tolerance, but cultivars developed for diverse growing environments may show variable susceptibility based on root vigor and nutrient uptake efficiency. Understanding nutrient-responsive genetics helps producers optimize feeding schedules for specific strain families without introducing deficiency stress during phenotype testing.