# Fems

> Fems is slang for feminised seed, made with pollen from a chemically sex-reversed female so nearly every plant grows female.

- Canonical: https://genetixbay.com/knowledge/glossary/fems.html
- Also written: femmed seed, fem seeds, femmies, fem, femmed
- Glossary category: Grower slang and culture · Evidence: Supported
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

Fems is slang for [feminised seed](https://genetixbay.com/knowledge/glossary/feminised-seed.md). A female plant (or branch) is treated so it makes pollen, usually with [silver thiosulfate](https://genetixbay.com/knowledge/glossary/sts.md) or [colloidal silver](https://genetixbay.com/knowledge/glossary/sex-reversal.md), and that pollen fertilises another female, or the same one in an [S1](https://genetixbay.com/knowledge/glossary/s1.md). The seed carries no Y chromosome, so nearly every plant is female.

## In practice

Fems suit growers with limited space who want every plant to flower. A 5-pack of fems should give 5 females. The quality of fems depends on the breeder's choice of which female to reverse: reversing a plant that never showed [intersex](https://genetixbay.com/knowledge/glossary/hermaphrodite.md) flowers, over a large test, is careful work; reversing whatever is popular is not.

## Don't confuse with

- **Regs**: regular seed with males and females.
- **Herm pollen seed**: seed from a plant that threw [bananas](https://genetixbay.com/knowledge/glossary/nanners.md) on its own. It is also "feminised" in a sense, but it is accidental and selects for intersex tendency.
- **Clones**: identical copies; fems are new individuals.

## Myth check

"Fems always herm." Not inherently. [Herm-prone](https://genetixbay.com/knowledge/glossary/herm-prone.md) fems come mainly from careless feminising and repeated selfing, not from the method itself. Ask for the line's tester [herm rate](https://genetixbay.com/knowledge/glossary/herm-threshold.md). See [feminised seed and sex reversal](https://genetixbay.com/knowledge/breeding/feminised-seed-sex-reversal.md).

## Related terms

[Feminised seed](https://genetixbay.com/knowledge/glossary/feminised-seed.md), [Regs](https://genetixbay.com/knowledge/glossary/regs.md), [Sex reversal](https://genetixbay.com/knowledge/glossary/sex-reversal.md), [Herm-prone](https://genetixbay.com/knowledge/glossary/herm-prone.md), [S1](https://genetixbay.com/knowledge/glossary/s1.md)

## Read more

- [Feminised seed and sex reversal: methods, with safety notes](https://genetixbay.com/knowledge/breeding/feminised-seed-sex-reversal.md)
- [Regular, feminised, autoflower or clone: choosing your starting material](https://genetixbay.com/knowledge/basics/seed-types-regular-feminised-auto-clone.md)