Anthurium F1, F2, S1 & S2 Explained: Understanding Anthurium Breeding Generations
Ever wondered what F1, F2, S1, S2 or BC1 actually mean when you see them on an Anthurium listing? Let's decode the breeding language behind the plants we collect, grow and love.
If you've been collecting Anthuriums for a while, you've probably come across labels like F1, F2, F3, S1, S2, BC1 and × self — and perhaps a few combinations that look more like a secret code than a plant description. 😂
But these little letters and numbers actually tell us something important about a plant: where it came from and how it was bred.
So is an F2 better than an F1? Is an S1 the same thing as an F2? And why can seedlings from the same Anthurium cross look completely different?
🌱 What Do F1, F2, S1 and S2 Actually Mean?
The letters describe the breeding pathway, while the numbers tell you which generation you're looking at.
Filial Generation
Used for offspring produced through crosses between different plants within a breeding line.
Selfed Generation
Used when a plant is pollinated with its own pollen and the resulting generations are selfed again.
Backcross
Used when a hybrid is crossed back toward one of its parents or a selected recurrent parent.
Self-Pollination
A common notation used by Anthurium breeders and collectors to indicate that a plant was selfed.
🌿 The most important thing to remember
F and S are not the same thing.
F generations come from crossing plants within a breeding line, while S generations come from self-pollination.
🌿 What Does F1 Mean in Anthuriums?
F1 means First Filial Generation.
It refers to offspring produced from the initial cross between two different parent plants.
For example: Anthurium crystallinum × Anthurium magnificum → F1
The resulting seedlings are the F1 generation of that particular cross. The parents may be different species or different individuals of the same species.
Are all F1 seedlings identical?
No. F1 seedlings from the same cross are siblings, not clones. Each seedling receives its own combination of genetic material from its parents, so variation can still occur.
However, compared with later generations such as F2, an F1 population can often appear relatively consistent, depending on the genetics of the parents and the traits being selected.
🌱 What Does F2 Mean in Anthuriums?
F2 means Second Filial Generation.
In a typical breeding programme, F2 offspring are produced by crossing F1 plants within the same breeding line.
This is very different from simply taking an F1 and self-pollinating it.
F1 × F1 = F2
F1 × itself = S1
Why can F2 seedlings look so different?
F2 populations can show much greater genetic segregation. Traits that were hidden or less obvious in earlier generations can appear among the offspring.
This can result in variation in:
- Leaf shape
- Vein expression
- Colour
- Texture
- Growth habit
- Size
- Overall plant morphology
This is one reason Anthurium seedlings from the same cross can look completely different. For collectors, that variation is often part of the excitement of growing from seed.
“An F2 population can become a treasure hunt for the traits you didn't know were hiding there.”
🌿 What About F3, F4 and Later Generations?
The same general concept continues:
Breeders can continue working within a particular line while selecting for desirable characteristics. The exact strategy can vary between breeding programmes, so generation labels should always be considered in the context of the breeder's documented lineage.
🌱 What Does S1 Mean?
S1 means First Selfed Generation.
Instead of crossing two different plants, the breeder uses pollen from the plant to pollinate itself.
You may also see this written as × self or selfed.
For example: Fairchild Crystallinum × self indicates that the plant was self-pollinated and produced a selfed seed generation.
If you'd like to understand the terminology in more detail, our guide to what “× self” means in Anthuriums explains exactly what this notation tells you about a plant's breeding history.
⚠️ S1 Is NOT the Same as F2
This is probably the single most important distinction to understand when reading Anthurium breeding labels.
Filial pathway
F1 × F1 within the breeding line produces the next filial generation.
Selfing pathway
Self-pollinating an F1 plant produces the first selfed generation of that plant.
So if you take an F1 Anthurium and self-pollinate it:
It does not become F2.
🌱 What Happens With S2 and S3?
The same principle continues:
Selfing is often used in breeding programmes to expose recessive characteristics and, over repeated generations, increase homozygosity and potentially increase uniformity for some traits.
However, selfing does not automatically create a better plant. It can also reveal unexpected or undesirable characteristics.
🌿 Is a Clone of an S1 Plant an S2?
🌱 No — a clone does not advance the generation.
If you have an S1 plant and take a genetically identical clone, the clone remains S1.
To produce S2 seed, you need to self the S1 plant and produce another generation from seed.
🔙 What Does BC Mean in Anthurium Breeding?
BC or Bx means backcross.
A backcross involves taking a hybrid and crossing it back toward one of its parents or another genetically similar recurrent parent.
If a BC1 plant is then crossed back toward the same recurrent parent, this can produce a BC2 generation.
For a deeper explanation of this breeding strategy, see our guide to what a backcross means in Anthurium breeding.
Why would a breeder use a backcross?
A breeder may use backcrossing when they want to move the offspring toward particular characteristics associated with one parent while retaining selected traits from the other side of the original hybrid.
In Anthuriums, this could be part of a breeding strategy focused on characteristics such as darker velvet, particular leaf architecture, compact growth or other selected traits.
🧬 Anthurium Breeding Cheat Sheet
| Label | Meaning | How it is produced | Typical use |
|---|---|---|---|
| F1 | First filial generation | Parent A × Parent B | Initial hybrid or cross within a breeding programme |
| F2 | Second filial generation | F1 × F1 within the line | Segregating generation with greater variation |
| F3 / F4 | Later filial generations | Continued breeding within the line | Further selection and development |
| S1 | First selfed generation | Plant × itself | Selfing, exposing recessive traits and breeding selection |
| S2 / S3 | Later selfed generations | Selfing S1, then S2, etc. | Further selfing and selection |
| BC1 / Bx1 | First backcross | Hybrid × selected parent | Move offspring toward a recurrent parent's traits |
| BC2 / Bx2 | Second backcross | BC1 × recurrent parent | Further backcrossing toward that parent |
🏷️ How Anthurium Breeders Write These Crosses
Once you understand the basic notation, plant labels become much easier to decode.
Species Cross
crystallinum × magnificum F1
The first generation from that cross.
Filial Cross
(crystallinum × magnificum) F2
A later filial generation within that breeding line.
Selfed Line
Fairchild Crystallinum × self
Indicates self-pollination.
Backcross
Hybrid × selected parent
Used to move the breeding line toward a particular parent.
🌱 Why F2 Anthuriums Can Be So Exciting
One of the most fascinating parts of growing Anthuriums from seed is watching variation appear.
Imagine growing ten, twenty or even fifty seedlings from the same breeding line. As they mature, they may begin to show differences in:
- Leaf shape
- Vein structure
- Texture
- Colour
- Growth habit
- Size
- Overall plant architecture
For a breeder, this variation can be incredibly valuable. The goal may be to identify one exceptional plant and use it as a parent for the next generation.
It's also important to remember that a young seedling may not reveal its eventual appearance immediately. Anthurium leaves can change shape as they mature, meaning juvenile foliage is only one stage of the plant's development.
Sometimes the most exciting seedling isn't the one with the fanciest label — it's the one that makes you stop and say, “Whoa… what is THAT?” 😍🌿
⚠️ F1 Doesn't Automatically Mean Better
Generation numbers are sometimes treated almost like quality grades. They aren't.
F2 isn't automatically better than F1.
S2 isn't automatically better than S1.
F3 isn't automatically better than F2.
These labels describe breeding history, not plant quality.
A spectacular F1 can be far more desirable than an average F2. Likewise, an exceptional S1 can be an extremely valuable breeding plant.
🔍 Why the Original Parents Matter
An “F2” label on its own doesn't tell you much.
Compare:
F2
You know the generation, but not the breeding history.
(crystallinum × magnificum) F2
You know which original cross the breeding line came from.
If you're buying a plant specifically for breeding, it's worth asking about the original parents and how the generation was produced.
This becomes even more important with complex hybrids, because you can't always tell what an Anthurium hybrid will look like simply by looking at its parent plants.
🌿 Breeding Notation You May Encounter
F, S and BC are the main terms, but Anthurium breeders and collectors may also use additional abbreviations, clone tags and line codes.
These may identify particular mother plants or breeding lines rather than generations themselves. For example, a breeder may use a personal line code to distinguish one selected plant from another.
You may also encounter more complex crosses such as:
(crystallinum × magnificum) × luxurians
This notation describes another cross involving the existing hybrid. Once multiple generations and parents are involved, keeping accurate breeding records becomes increasingly important.
🌱 Why Understanding This Makes Collecting More Interesting
Once you understand what these little letters and numbers mean, plant labels start telling you a story.
Instead of simply seeing:
“F2 Anthurium hybrid”
you can start asking:
- What was the original cross?
- Which plants were selected?
- What traits was the breeder trying to reproduce?
- Was this generation produced through crossing or selfing?
- What makes this particular seedling special?
If you're new to buying young Anthuriums, it can also help to understand the difference between an Anthurium seedling and a clone. A generation label describes breeding history, while seedling versus clone describes how the plant itself was propagated.
And that's where Anthurium breeding gets really fascinating.
You're not simply growing a plant.
You're watching a genetic story unfold over generations. 🌱🧬
🌿 F1 vs F2 vs S1 — The Quick Version
If you remember nothing else, remember this:
❓ Frequently Asked Questions
What does F1 mean in Anthuriums?
F1 means First Filial Generation and generally refers to offspring produced from the initial cross between two distinct parent plants.
What does F2 mean in Anthuriums?
F2 means Second Filial Generation. In a typical breeding programme, it is produced by crossing F1 plants within the same breeding line.
Is F2 the same as selfing an F1 Anthurium?
No. Selfing an F1 produces an S1, while crossing F1 plants within the breeding line produces an F2.
What does S1 mean in Anthuriums?
S1 means First Selfed Generation. It is produced when a plant is pollinated with its own pollen.
What does S2 mean?
S2 is the next selfed generation produced from an S1 plant through self-pollination.
Is a clone of an S1 plant an S2?
No. A clone remains genetically part of the same generation. An S1 clone is still S1. Seed produced by selfing that S1 plant is S2.
What does BC1 mean in Anthurium breeding?
BC1 means First Backcross Generation, where a hybrid is crossed back toward a selected parent.
Is an F2 Anthurium better than an F1?
Not necessarily. F1, F2, S1 and other labels describe breeding history rather than plant quality.
Why do F2 Anthuriums vary so much?
F2 generations can show greater genetic segregation, allowing different combinations of traits to appear among seedlings.
Why should I ask for the original parents when buying an F2?
Because an F2 label is relative to a particular breeding line. Knowing the original parents gives you much more useful information about the plant's ancestry.
🌱 Final Thoughts
F1, F2, S1, S2 and BC might look confusing at first, but the basic idea is actually quite simple.
F = filial generations created through crosses within a breeding line.
S = generations created through self-pollination.
BC / Bx = backcrossing toward a selected parent.
The number tells you where that plant sits within that particular breeding pathway.
Most importantly, don't look at the generation number as a measure of quality. Look at the parents, the lineage, the traits and the breeder's selection process.
Because sometimes the most exciting Anthurium in a whole tray isn't the one with the fanciest generation label…
It's the one that makes you stop and say, “Whoa… what is THAT?” 😍🌿