- Selectively Breeding Pepper Plants
- What is Selective Breeding?
- What’s Going On Behind the Scenes?
- Things to Keep in Mind
- Additional Resources
- Going to Seed with Dan Brisebois
- How to proper pollinate peppers?
- Flowering and Pollinating Chilli Plants
Crossing and Breeding Chile Peppers
(how to create your own hybrids!)
Anatomy of the chile pepper flower
e. blossom end
Ok, enough about the science, let’s get into some action!
Here’s a simple way how to breed your own varieties by mixing your
First, make a decision about the varieties you’d like to test.
At first, it’s good to select varieties which have as different pods as possible,
that way you’ll be able to see the differences between the properties more easily.
Also, it’s good to select the varieties within the same species first, it’s
much easier to learn that way compared with the mixed species.
1. Select a flower from the variety you want to use as a male with the breeding.
Here’s C. annuum var. ‘Malawi Bird’s Eye’
2. Then, select a flower from the variety you want to use as a female with the breeding.
C. annuum var. ‘Cayenne’ works as a female here.
3. Use forceps to remove the petals from the closed female flower bud.
3. Half of the petals removed.
4. All petals removed.
5. Ok, now it’s time to start emasculating!
Use forceps to pick off the stamens, but
be very careful not to damage the pistil on the middle of the blossom end.
Magnifying glass might be useful here, especially with smaller-flowered
6. Removing the last stamen.
Now you can see pistil left on the flower.
This flower is a pure female now.
It would be a good thing to emasculate more flowers from this
plant to increase the change of succeeding with pollinating.
7. Then, use a cotton stick to collect some pollen from the stamens
of the variety you’re using as a male.
8. Transfer the pollen to the stigma (tip) of the pistil, and
we’re almost done!
(Pollinate all of the emasculated flowers you have on this plant.)
9. Final stage is to label the cross.
The first variety name on the label will tell which one is the female.
Within the next week or so the flowers will fall off if the cross won’t take.
In other case, you’ll have the seeds for your cross after the pod has matured!
After germinating the crossed seeds you’ll be able to see the results of the cross.
If this isn’t interesting and fun, then what is?
Capsicum crossability matrix
This table shows the end results possible with various crosses of different pepper species.
|Male Parent||Female Parent|
NG = F1 hybrids germinate normally
(Reproduced from Figure 3, Genetic Resources of Capsicum,
International Board for Plant Genetic Resources, 1983 )
Instructions by: Fatalii
Photos by: Jussi Laakso
Selectively Breeding Pepper Plants
Our 2019 attempt to continue selectively breeding our fury pepper (F4 & F5) – originally was an accidental white ghost hybrid
Have you ever had a pepper plant that was “different” in a way that made it one of your favorites – a pepper plant you’d like to grow year after year? Perhaps, it was an accidental or purposely created hybrid. Or, it was simply a traditional pepper cultivar that happened to have larger fruit, better flavor, or a higher yield.
Now what? You could take cuttings to clone the plant. You’d be guaranteed an exact genetic copy, though, cloning attempts don’t always root successfully – and overwintering the cuttings potentially creates other issues.
It’d be more convenient to take its seeds and attempt to grow it again next year. The problem is that there’s no guarantee the resulting pepper plants will share the desired traits of their parent. That’s where the process of selective breeding comes in.
What is Selective Breeding?
Selective breeding has been used by humans for thousands of years. It’s the process Native Americans used to turn a grass-like plant into modern day corn. These same early civilizations used selective breeding to domesticate small, berry-like wild peppers into the habanero, jalapeno and many of the other popular varieties we now enjoy. The intertwined processes of hybridization, random mutations, natural selection and selective breeding have produced an estimated 50,000 varieties of chile peppers!
Where hybridization and random mutations introduce newness, it’s the processes of natural selection and selective breeding that choose which traits endure.
Simply put, selective breeding is a numbers game – take seeds from parent plant(s) with desirable trait(s) and grow a bunch of plants from them. Evaluate the plants and chose the ones that best express the intended traits to self or cross pollinate. Harvest those seeds and repeat the process. Carried out over several to many successive generations, this process can magnify and lock-in the traits desired.
What’s Going On Behind the Scenes?
The original “different” plant that produced the desirable traits, was different due to different genetics (assuming it wasn’t due to different growing conditions). The difference in genetics was either due to hybridization, a pairing of rare recessive traits, or random genetic mutation(s). This first generation plant is referred to as F1, or the first filial generation. Seeds taken from this first generation plant will be the second filial generation, or F2. Seeds taken from that generation, are referred to as F3 seeds that’ll produce F3 plants, and so on.
The earlier generations of these plants hold genetic differences that may, or may not, express themselves in the seeds taken from their pods – even in the event of self-pollination. Early generations are less likely to consistently produce offspring with the desired traits, and are less likely to do so to the fullest extent. This is especially true for F2 hybrid plants, which theoretically, should have the greatest differences among its siblings. Due to the intricacies of genetic science (which we’re not going to dive into), the more generations into the process of trait selection, the more likely those traits are to express themselves within the following generation.
Our research suggests once the selection process is successfully carried through to its 7th generation (F7), the seeds from those plants (F8) should reliably produce plants with the desired traits. By this point, the pepper plant should be a nearly homozygous cultivar – meaning its corresponding chromosome pairs should be nearly identical – and reliably produce seeds that “come true” to produce matching offspring plants.
Things to Keep in Mind
As mentioned, selective breeding is a numbers game. The greater the number of offspring plants grown each generation, the better the odds of maximizing the desired traits. We have somewhat limited space for growing peppers, though we’ve had good results with 6-10 plants per generation. We now target growing 10 plants per generation, while keeping more seeds on-hand in the event additional plants are needed.
It’s also important to note the selective breeding process assumes steps are taken to avoid accidental hybridization. The desired plant(s) should be isolated from other pepper plants to ensure either self-pollination or intended cross-pollination occurs.
To maximize trait expression and to produce hardier plants, the top two, or three, plants of a generation should be crossed with each other. This helps to expand the genetic diversity, which provides for a greater genetic base for maximizing desired traits. Along with color, shape, flavor, heat-level and yield, one should also consider including hardiness, disease resistance and germination rates when grading plants for selection.
Our Experiments with Selective Breeding
Stumbling upon interesting hybrids and attempting to selectively breed them into repeatable varieties is one of our favorite aspects of growing peppers. Below are the two main strains we are currently working to develop.
Fury Pepper (F5 & F4)
Fury, F4 pepper w/ F5 seeds
Pictured at the top of this page is our 2019 batch of F5 and F4 fury pepper seedlings. We’re currently working with two strains as the F4 variety (F5 seedlings) produced the intended pod-type, but it was less hot than previous generations and had slightly less yield and lower perceived hardiness. The F3 variety (F4 seedlings) had a different pod-type (elongated), but nice heat and hardiness paired with an amazing yield.
This strain originally started as an accidental hybrid of a white ghost, and we believe, a yellow Trinidad scorpion. It’s one of our all-time favorite peppers. In previous years, we’d grown four through eight plants per generation, and until last year, always had one express the full set of desired traits to select. We’re growing ten this year – five each of F4 and F5 – in hopes we’ll have two to cross and propagate.
Peach Pepper (F1)
Peach hybrid, F1
If we’re able to successfully reproduce this pepper, it’ll easily be one of our favorites. It’s definitely the sweetest and among the juiciest we’ve ever had. For the first few seconds, it produces almost no heat – but it quickly builds to an almost intolerable level a minute in. It’s a smaller plant with medium-sized, peach-colored fruit and sports a decent yield.
This pepper popped up unexpectedly last year (2018). We were attempting to grow a hybrid of a hybrid of an Australian lantern that we believe crossed with our original mystery pepper (got seeds at a chili cookoff and weren’t able to identify the variety). We were expecting red, mini, bell-like peppers with good heat, but were pleasantly surprised to get this instead. The prior year, we were growing a flaming icicle nearby and perhaps that mixed in.
We’re growing ten offspring plants this year in hopes of getting a matching plant, or two.
- Basic Growing Guide / Quick Growing Tips
- Step-by-Step Growing Guide
- Cloning Pepper Plants
- Hybrid Pepper Plants
Going to Seed with Dan Brisebois
Seven or eight years ago I planted some Bulgarian Carrot Hot Pepper seeds from Fedco. Most of the plants had elongated orange fruit similar to Cayenne peppers but with more flesh. One plant was covered with fruit that were round and squat though equally orange and spicy. This rogue pepper plant was likely due to an accidental cross in the seed growers garden.
Of course, I saved the seed from this rogue hot pepper – essentially a F1 cross. This is where things got messy. When you save F1 seed from, you get a lot of variation in subsequent generations. Only by consistently saving seed from plants that look similar over a number of generations do varieties start to stabilize.
The impact and diversity from my carrot pepper selections each generation have brought me to pay more attention to each plant in a population and try to find ways to easily record the changes (essentially accurate labeling and taking pictures.)
(For more crossed up plant, you can read my post on crossed-up lettuces
Growing Out Crossed-Up Peppers
Nowadays, in the early generations after a cross I save the seeds from each selected hot pepper plant separately. The next year I grow 10-20 plants of each selection in the garden.
I grow each selection in a row divided from the previous selection with a stake.
Over the season, I evaluate each plant in each selection to see how uniform the selection is and whether any individual plants stand out. If the selection is very uniform I might mix the seed from the best plants together. If there is still quite a bit of diversity, I keep the seed from individual plants separate.
Let’s see what that looked like in 2011 and 2012
2011 Carrot Pepper CrosseS
In 2011, I selected 6 different plants. Each plant is labeled in the picture. The first plant labeled F3 6-1. F3 means the plants is from the F3 generation. 6-1 means the plant is the first plant selected in 2011 from the 6th plant in 2010. These 6 plants were all from 6th or 7th selection made in 2010.
Plants 6-1, 6-2, 6-3 and 6-4 are therefore siblings. These plants are cousins with 7-1 and 7-2.
2012 Carrot Pepper CrosseS
In 2012, due to space constraints I only grew 5 plants of each selection. For each strain I first took a picture of the plants:
This gave me a quick idea of the relative yield, color variations, pod shape, and whether the fruits grows upwards or hangs down.
Next I pulled the fruit off of each plant and took another picture:
This let me see how fruit variation was still present. Pods pointing down indicated hanging fruits, pods pointing up indicated upwards fruit.
This also lets me compare the 2012 fruits with my 2011 picture above. In general you can see there’s less variation within each of the following 2012 selections than in 2011.
At this point I’ve selected different plants to save fruit from based on pod characteristics, plant structure, yield, and earliness (I’d previously tagged the first plants with mature fruit.)
I put the fruits from each of my selection into a separate quart to later extract the seed.
This picture is actually from another set of selections in the F6 generation.
The culled fruit go into a bin…
and then head to market or CSA!
One Other Selection Consideration
Before extracting seed from each selection, I taste each fruit. I start with the fruit bottom, then the side wall, and finally the core to see how hot these peppers are.
I started doing this after I realized a Jalapeno I was working with had lost almost all of its heat. After selecting by taste for a future generations, most peppers are consistently and adequately hot.
Needless to say this tasting happens over a few days. As it takes me 10-15 minutes after each “winner” before I can taste another pepper’s heat.
A Word About Isolation Distance
Most of the peppers we grow are destined for eating. As such we grow these varieties side by side with no isolation distance. Though peppers are predominantly self-pollinating, there can still be low amounts of cross-pollination with plants grown this close together. Still I save seed from these peppers for our own farm use. Most of the time I don’t see any crossing, but when I do I get excited!
I should mention that I always grow hot peppers a good 200′-600′ away from our sweet peppers. This ensures our sweet peppers stay sweet and our hot peppers stay hot. Also, any hot peppers we grow to sell as seed are grown with 200′-600′ isolation distance since we want to keep these varieties pure.
What Else Has Been Going on In Dan’s Life?
You may have noticed I haven’t been posting much lately. Part of that of course is due to the growing season, and playing with hot peppers; and of course planning for the Nov 9-10-11 Seed Connections conference in Montreal; but mainly (and most importantly) Emily and I now have a little daughter named Stella in our life! You can see some pictures in the recent Tourne-Sol newsletter.
(Dean Fosdick via AP)
QUESTION: Is it true that if you plant hot peppers on the same row as sweet peppers, the sweet pepper plants will cross with the hot peppers and become hot? — William Carver
ANSWER: I get variations on this question all of the time. Will yellow squash cross with nearby zucchini plants to produce odd squashes? Will my lemon tree cross with a nearby orange tree and produce orangey-lemons or lemony-oranges? While it’s certainly possible for cross pollination to take place between these plants, it does not affect the type of fruit a plant produces.
The fruit depends entirely on the genetics of the plant producing the fruit, not where the pollen came from to pollinate the flowers.
Although peppers are self-pollinating and generally do not cross, sweet peppers and hot peppers belong to the same species and can cross with one another. If pollen from a hot pepper fertilizes the flower of a sweet pepper, all of the hot pepper genes from the father plant go into the embryo and the seed. The genes from the male parent do not play a part in the formation of the fruit. That depends entirely on the genetics of the mother plant. The fruit of the pepper plant develops from the ovary of the flower of the mother plant. The heat or mildness of the pepper itself is strictly determined by the genes of the mother. In other words, if a flower of a sweet pepper is pollinated by a hot pepper plant, it absolutely, positively will not make the sweet pepper hot.
Now, if you plant the seeds inside that sweet pepper then you will see the effect of the male parent’s genes. The embryos inside the seeds inherited half their genetic makeup from the male parent. That means it is likely that plants grown from the seeds may turn out hot. So if cross pollination does occur between a sweet and hot pepper, it does not affect the fruit produced, but may affect the characteristics of the next generation.
This information applies to all vegetables (other than corn), including squash and zucchini, and all fruit, such as lemons and oranges. Cross pollination is not an issue.
Dan Gill is a horticulturist with the LSU AgCenter.
Tomato plants are self pollinating and they produce flowers with both male and female organs allowing the pollen to be shed directly onto the stigma of the flower. Tomato plants are most commonly pollinated by the wind or by bees but may occasionally need a helping hand to release their pollen in gardens which are very sheltered, or if plants are kept indoors or in a glasshouse. Hand pollination of tomatoes is a simple process and it should be conducted on a warm sunny day for optimal results. You can simply shake the flowers by tapping behind the flower with your finger or with a pencil to stimulate the plant to release pollen. Do this for 2-3 consecutive days to ensure that the pollination has been successful. Some people prefer to collect the pollen that is released in a container and transfer it to the stigma of the flower using a soft brush such as a paintbrush. Collected pollen can be stored in the fridge for a couple of days. Another commonly used technique is to use an electric toothbrush to vibrate the flowers. The toothbrush should be touched against the plant just behind the flower for a few seconds. Do this at least once a day. You will know that successful pollination has taken place when the flower begins to shrivel and fruits begin to form.
In the case of pepper plants, as self pollinators, they can be pollinated in much the same way as tomatoes although it is rarely necessary. Some gentle flicking of the flowers should be all that is required. You may also use a soft paintbrush to transfer pollen to the stigma.
Squash plants produce both male and female flowers on the same plant and if there is a lack of natural pollinators such as bees, or if it is important to produce seed that is true to type (i.e. genetically similar to the parent and not cross pollinated by an unrelated plant), then you may wish to practise hand pollinating. The first thing you should do is identify the male and the female flowers. This should be relatively straightforward, female flowers possess a swollen ovary at their base which will eventually produce the fruit, male flowers do not. If you simply wish to give the flowers a helping hand then you can use the paintbrush technique to transfer pollen from a male flower to a female or you can pick a male flower and remove its petals to expose the pollen-containing anthers before rubbing the pollen onto the stigma of the female flower. When attempting to produce true to type seed then this process may be used, but it is necessary to prevent cross pollination by taping flowers closed both before and after you hand pollinate.
How to proper pollinate peppers?
Ive seen a couple of videos of how to pollinate tomato and peppers, generally they just shake the plant or the flower, and as tomato and pepers are self-polinating they grow fruit….. it worked with my tomatoes, but i dont think its working with the peppers:
I tried to shake the plant, the flower, and even get a little cotton swab to manually transfer the pollen inside the flower… the only thing that i got its the flower falling and leaving the little green ball, that ends falling a couple of days later (This happen with the 3 or 6 flowers that first appear)
Latelly i got a little change, in this case (didnt do anything different) the flowers just dry up but they dont fall:
I dont know if im doing it right, and its a little confusing since some people say’s that peppers have a male / female flower and that you should transfer pollen between them… and other people say’s that the flower its male / female at the same time, and you just need a little movement to pollinate the flower… so any tips?
My peppers are the big sweeter one’s, california wonder peppers 😀
Thank you all for your answers….. i wasnt getting fruit because those where the first flowers of the plant and die even if they are pollinated, the newer ones are finally producing fruit!
We are finally getting the right weather to ripen tomatoes, zucchini, peppers, basil and a whole host of other warm-season crops. We will get a bump into the 90s for a few days and then another stretch of 80s into next week. The best news is that the night temperatures aren’t getting below 55 degrees, which is critical for some warm-season crops to set fruit.
With the cool start of summer, we’ve lost a lot of growing time and the next four weeks will be critical to getting a crop. Our summer weather begins to cool after the middle of August, especially at night. So it’s time to practice a little intervention to help the plants set fruit.
Honeybees, native bees and other insects are responsible for much of the pollination of vegetable plants. That’s why there has been so much concern about protecting them and providing habitat. While most of the habitat development is done in the spring, you can help them out now by providing them water in a large container with gently sloping edges that is regularly refilled with a dripper. I have a leaky sprinkler pipe that fills a depression that they really like.
You can also help out by doing a little hand-pollinating with an old electric toothbrush. Tomatoes and peppers have both male and female parts in the flower, which means it is relatively easy for moving air or a visiting bumblebee to transfer the pollen. To help the process along, place the toothbrush head just behind a flower cluster and turn it on “brush” for three to four seconds. This vibrates the flower and shakes loose the pollen. Repeat to other clusters of flowers. Check back in a week to see if there are tiny tomatoes forming. This same process can be used on peppers.
Cucumbers and squash can also be pollinated by hand to encourage fruit set. These plants have separate male and female flowers on the same plant. A female flower will have a swollen area just below the base of the flower that, when pollinated, will swell into a fruit. The male flowers won’t have any swelling at their base and often bloom well before the female flowers. There are probably a lot of plants out there right now covered in male flowers.
Hand-pollinating squash, melons and cucumber also involves moving pollen from the male flower to the female. Find a male flower, the one without the bulge at the base, and gently remove all the petals so you have just the anther covered in yellow pollen. Gently open the petals a little on the female flower and tap the anther on the stigma in the center of the flower. This will transfer the pollen and fertilize the flower. Again, check back in a week or so for signs of tiny new fruits.
Lastly, basil is finally getting the really warm weather it needs, so apply some 10-10-10 fertilizer or blood meal now to encourage growth.
Pat Munts is co-author, with Susan Mulvihill, of the “Northwest Gardener’s Handbook.” Munts can be reached at [email protected] gardening.com.
Flowering and Pollinating Chilli Plants
It does not matter how many chilli plants I grow or have grown I am still left in awe at the outstanding beauty these flowers can show
Often no bigger than your finger nail but with such striking colours they are for me Queens in the flower world
Especially as from natures best you get berries being grown that bring such pain!
Growing Plants Indoors or in a Glass Greenhouse
By growing in front of Glass the temperature range can vary above 10c
Chilli Plants respond to temperature variation that triggers it genes to click on and off
This means the plant will grow vegetation and/or flowers, if it is starting to flower and then the plant experiences at least a 10c temperature variation then its flowering genes will be switched off and the vegetation gene will continue
This has an effect of stopping the new flower heads being sent nutrients so they die and drop off
Often there is little we can do to stop this as we are growing on the windowsill as that is the only place we have to grow in
You can try to alter the temperature in the room with opening windows, removing the plants from directly next to the window in the afternoon to cool the plant down and reduce the temperature variation, but the affects will still continue
This does not mean all your flowers will drop off though, if you provide the right nutrients and the soil you will get plenty of days when the temperature variation is not greater than 10c and you will still get plenty of pods growing to satisfy you
For a full explanation of what is happening please see our guide on Humidity and VPD
If you are growing outside or in a polytunnel then the temperature variation will be reduce greatly, it may still have a day or two where it is greater than 10c but flower drop off will be only be on the occasional one rather than a few
Chilli Flower Sex
So how does a Chilli Plant reproduce?
Chilli Plants are self pollinating; producing both female and male parts, the picture below describes the parts of a chilli flower
c.) pistil (Female)
d.) stamens (Male)
e.) blossom end
The stamens produce Pollen Sacs which open up and start to spread pollen through wind and insect contact
Once the pollen comes into contact with the stigma which is the tip of the pistil the flower becomes pregnant!
How to assist with pollinating chilli flowers
Once you see your flowers starting to produce pollen you can take a cotton wool bud as you see in the picture and gently brush the cotton against the pollen sacs
This will collect pollen which you can then brush against the tip of the pistil or the stigma
You can take the same bud and pollinate all the flowers on the same plant
If you take pollen from one type of chilli and use it on another different chilli plant then you may cross breed
Once the flower has been pollinated it only takes a couple of days to go from the moment of conception to the pod starting to be produced
The flower petals will start to droop and go brown as they die
The pod will start to push through from the calyx which is in effect the plants umbilical cord to provide nutrients to the chilli being grown