Fan Leaves
Definition: Fan leaves are the large, hand-shaped leaves of a cannabis plant, made of several serrated leaflets that radiate from a single stem. They are the plant's main solar panels, producing most of the sugars that fuel growth and bud production. Fan leaves carry few trichomes and are usually removed and discarded at harvest.
How Fan Leaves works
A mature fan leaf typically has 5 to 9 leaflets, though some plants grow 11 or 13. Leaflet shape hints at genetics: broad, dark, overlapping leaflets usually point to indica ancestry, while long, slender, lighter ones suggest sativa heritage. Most modern hybrids fall somewhere between.
Reading plant health
Fan leaves are the first place problems show, which makes them a built-in diagnostic tool.
- Yellowing from the bottom up in veg: often nitrogen deficiency.
- Burnt, crispy tips: usually too much fertilizer, a sign of nutrient burn.
- Leaves praying upward: typically a happy, well-lit plant. Drooping and limp can mean thirst or overwatering.
- Rust spots or curling edges: check pH, heat and light distance.
Remove or keep?
Fan leaves store nutrients and feed the buds, so do not strip them without reason. Selective defoliation helps when leaves block light from bud sites or choke airflow, commonly done just before the flip and again around day 21 of flower. In the last 2 to 3 weeks, fans naturally yellow as the plant pulls their stored nitrogen, a normal fade rather than a deficiency.