# What are pistils?

> Pistils are the female reproductive organs of cannabis flowers. The white or coloured 'hairs' growers call pistils are strictly the stigmas: each female flower has two, sticking out of its bract to catch pollen. They appear first at the nodes as preflowers, then by the hundred in buds, and darken through orange or brown with age, heat or pollination. Judge harvest by trichomes, not pistil colour.

- Canonical: https://genetixbay.com/knowledge/answers/what-are-pistils.html
- Topic: Basics · Type: Definition
- Evidence: Established · Status: Draft: awaiting expert review
- Full article: [Cannabis plant biology: the parts and what they do](https://genetixbay.com/knowledge/basics/cannabis-plant-biology.md)
- Also asked as: Pistils meaning | White hairs on buds | Stigmas on cannabis | Why are my pistils turning orange?
- Updated: 2026-10-31 · Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay Knowledge Base (genetixbay.com/knowledge)"

## Short answer

A [pistil](https://genetixbay.com/knowledge/glossary/pistil.md) is the female part of a flower: ovary, style and [stigmas](https://genetixbay.com/knowledge/glossary/stigma.md). On cannabis, the white or coloured "hairs" growers call pistils are the stigmas, two per flower, reaching out of the [bract](https://genetixbay.com/knowledge/glossary/bract.md) to catch pollen. They darken with age. *Established* botany.

## Why

Each [female flower](https://genetixbay.com/knowledge/glossary/pistillate-flower.md) is simple. One ovary sits inside a small leafy bract (the "[calyx](https://genetixbay.com/knowledge/glossary/calyx.md)" to growers), topped by two long stigmas [2]. A [pollinated](https://genetixbay.com/knowledge/glossary/pollination.md) flower makes a single seed.

Pistils show sex first. Single flowers form at the nodes once the plant matures; in one cultivar the first pair appeared at the 7th node, whatever the [day length](https://genetixbay.com/knowledge/glossary/photoperiod.md) [3]. Paired white hairs at a node mean female.

Clusters of pistils mark real flowering. On photoperiod plants, at least three pairs of pistils at the top of the main shoot is the research definition of flowering onset, usually 8–14 days after short days begin [1].

The resin isn't on the hairs. Glandular [trichomes](https://genetixbay.com/knowledge/glossary/trichome.md), densest on the bracts, make the [cannabinoids](https://genetixbay.com/knowledge/glossary/cannabinoid.md) and [terpenes](https://genetixbay.com/knowledge/glossary/terpene.md) [4]. That's why trichome maturity, not stigma colour, is the better harvest clock.

## The numbers

| Stage | What pistils look like |
|---|---|
| [Preflower](https://genetixbay.com/knowledge/glossary/pre-flower.md) (~4–6 weeks from seed) | One pair of white hairs at a node |
| Onset of flower (~10–14 days after flip) | 3+ pairs clustered at the top |
| Mid flower | Masses of fresh white stigmas |
| Late flower | Most curled, orange, red or brown |
| Pollinated flower | Withers and browns within days |

## What to do

1. Use paired white hairs at the nodes to identify females.
2. Log the day pistils cluster at the top as day 1 of flower.
3. Treat sudden, early browning as a stress clue: check heat and [RH](https://genetixbay.com/knowledge/glossary/relative-humidity.md).
4. Decide harvest with a 60x [loupe](https://genetixbay.com/knowledge/glossary/jewelers-loupe.md) on the [trichome heads](https://genetixbay.com/knowledge/glossary/trichome-heads.md).

## Common mistakes

- Harvesting by pistil colour alone.
- Calling the bract and stigmas "the pistil" and expecting resin there.
- Confusing stipules at the nodes with preflowers.

## Related

- Full article: [Cannabis plant biology](https://genetixbay.com/knowledge/basics/cannabis-plant-biology.md)
- Answers: [pistils browning early](https://genetixbay.com/knowledge/answers/pistils-turning-brown-early.md) · [checking trichomes](https://genetixbay.com/knowledge/answers/how-to-check-trichomes.md) · [when plants show sex](https://genetixbay.com/knowledge/answers/when-do-plants-show-sex.md)
- Article: [Trichome ripeness](https://genetixbay.com/knowledge/harvest-cure/trichome-ripeness.md)
- Terms: [pistil](https://genetixbay.com/knowledge/glossary/pistil.md) · [stigma](https://genetixbay.com/knowledge/glossary/stigma.md) · [bract](https://genetixbay.com/knowledge/glossary/bract.md)

## Follow-up questions

**When do pistils first appear?** Pistils first appear as single preflowers at the nodes once a cannabis plant matures, usually about 4–6 weeks from seed under long days, and around the 7th node in one study. On a photoperiod plant, clusters of pistils at the top of the main shoot appear about 10–14 days after the switch to 12/12, marking the real start of flower.

**Why are my pistils turning brown?** Cannabis pistils turn brown or orange as the flowers age, which is normal in the last weeks of flower. They also darken early from heat, low humidity, handling, sprays or pollination, which withers the stigmas of fertilised flowers within days. Browning on its own is a weak harvest guide; check trichome heads with a 60x loupe instead.

**Should I harvest when 70% of pistils are brown?** 'Harvest when 70–90% of pistils are brown' is a rough rule, not a reliable one, because pistil colour also changes with heat, handling, humidity and cultivar. GenetixBay judges harvest by trichome heads: a few clear, mostly cloudy and some amber is a good mix, with the exact balance a matter of preference.

## Sources

1. Spitzer-Rimon B, Duchin S, Bernstein N, Kamenetsky R. 2019. Architecture and florogenesis in female Cannabis sativa plants. Frontiers in Plant Science 10:350. https://doi.org/10.3389/fpls.2019.00350
2. Small E. 2015. Evolution and classification of Cannabis sativa (marijuana, hemp) in relation to human utilization. Botanical Review 81:189-294. https://doi.org/10.1007/s12229-015-9157-3
3. Spitzer-Rimon B, Shafran-Tomer H, Gottlieb GH, et al. 2022. Non-photoperiodic transition of female cannabis seedlings from juvenile to adult reproductive stage. Plant Reproduction 35(4):265-277. https://doi.org/10.1007/s00497-022-00449-0
4. Livingston SJ, Quilichini TD, Booth JK, et al. 2020. Cannabis glandular trichomes alter morphology and metabolite content during flower maturation. The Plant Journal 101(1):37-56. https://doi.org/10.1111/tpj.14516