How to Crossbreed Peppers

Capsicum are plants with flowers that contain both Female and Male reproductive organs. This effectively means that Capsicum are able to self pollinate and do not require another plant to fertilize the flowers.

This having been said, Capsicum can also be pollinated by other Capsicum plants nearby via wind or insects. This effectively makes peppers super hybridizers – and they do.

But you may wish to intentionally create a cross between two cultivars to create a new strain. To do this, plants can be manually hand pollinated to ensure best results.

The most important aspect of this process is to ensure that the possibility of unintended pollination is excluded. So one needs to enure that none of the flowers that will be used in this process have been exposed to pollen from another plant or its own pollen.

To do this, we are going to be dealing with flowers that have not yet opened. Unopened flowers are not at risk of pollination as the Stigma is effectively sealed off to the open environment by the petals that surround it. And while the flower is still closed the Anthers will not have any viable pollen that can pollinate the Stigma.

We have included a simple diagram to familiarize yourself with the various parts that make up the capsicum flower.

Tools Required:

• Two Plants (Presumably different cultivars, for best results – stable cultivars)
• Blossom Bag (no smaller than 10x10cm)
• Pointed Tweezers (pointed for precision)
• Disposable Earbuds
• Lightweight Twine or small tags

PLEASE NOTE: This procedure should be performed on the plant. For ease of demonstration, we are showing flowers that have been removed from the plant.

Manual Hand Pollination

This procedure should be used in an instance where you want to make absolutely sure that your intended cross is true. As already previously stated, this process eliminates the possibility of other pollen being part of the equation.

For this procedure we will require two plants. One plant which will be donating the pollen and one plant which will be receiving the pollen. Seeing your intention is to create a cross between two different cultivars, both plants will represent the different cultivars. (ie: Plant A = Habanero and Plant B = Jalapeno)

Ideally we want both plants to have flowers that are closed and almost ready to flower. First step is to isolate the donor plant. This is the plant that will be providing the pollen. This will happen roughly two days before the intended cross.

1) Locate a flower on the donor plant that has not yet opened but looks like it is about to open shortly. This is going to be our pollen donor. For the pollen to become available, this flower will need to open and the pollen will need to be available. It will take about two days for this process to take place.

To avoid any possibility of contamination from other pollen, we will isolate the closed donor flower with a Blossom Bag. For this, we will place the Blossom Bag over the unopened flower and tie the bag off to ensure no foreign pollen can get into the bag.

 

2) The closed flower will open inside the Blossom Bag over the next day or two and will usually start producing pollen late afternoon (the hottest part of the day 12:00 - 15:00). You will notice that the Anthers of the flower will be covered in a powdery substance.

Note the size of the pollen bag versus the flower. The flower has lots of room. If your Pollen Bag is too small it will stifle the flower. Temperature surrounding the flower may rise and a tendency for flower drop may increase. Ensure your bag is no smaller than 10x10cm!

We will now be able to harvest the pollen from this flower!

 

3) Carefully loosen the Blossom Bag around the donor flower and taking an unused earbud, gently pick up pollen from the open flower on the plant. For this to happen, you will need to brush the earbud against the Anthers.

Pollen is a very very fine dust that will appear as a white to off-white dust.

Once you have harvested the pollen from the donor plant, it is important to do the next step as quickly as possible to ensure the pollen is fresh and optimal.

4) Now locate a closed flower on the recipient plant (as above). This will be the receptor of the pollen you have just collected.



5) Using the tweezers, carefully remove the outer petals of the closed flower. A steady hand is required. Remove all the petals so you are left with the Stamen and the Stigma in the centre.



6) Using the tweezers carefully remove all of the the Stamen surrounding the Stigma - making sure not to damage the Stigma in the middle. Once all the Stamen have been removed, all that will be visible is the Stigma coming out from the top of the Ovary.

7) Take the earbud with the pollen on it and very very gently dab the Stigma of the flower you removed the petals and stamen from.

NB: You can use the same earbud for different flowers on the same variety. But, never use the same earbud between different varieties as you will effectively be transferring pollen from one variety to another ie cross pollinating varieties.

8) Once done, tie a loop of twine around the stem of the pollinated flower. Do not tie the twine too tight. The twine should be loose. This serves only as a marker so later when the pod starts fruiting, you can tell (and know) which pods were derived from flowers that were self pollinated. Plants have flowers that open every hour of the day so it is not feasible to catch them all before they open. This way you will be able to distinguish the hand pollinated pods that will be guaranteed self pollinated.

You may also wish to add a label of sorts to write on. Should you be doing lots of crosses, it is good to record what cultivars were crossed.

Don’t be disappointed if this process is unsuccessful at first. Pollination is not guaranteed and may result in the flower dropping off. This happens and is quite normal. It is best to pollinate a few flowers at a time to cover all the bases.

All things being well, the Ovary will swell and a pod will develop.

You may be expecting this pod to be different to the Mother plant’s pods, but this will not be the case. If the pollen has taken, the developing pod will look – exactly – like all other pods on the mother plant. This is normal. What you can not see is that the genetics of the donor plant are now in the seeds within this pod.

The resultant harvested seeds from this pod can now be sown on to create plants that will have genetics from both parent plants. Each seed will contain different genetic traits from each parent plant to varying degrees. This will become evident when plants grow from these seeds.

You will now embark on a process to grow out the desired genetics from the various different plants and narrow down the desired genetics until you stabilize the new genetics. This will happen over many growing seasons. This process is fun and filled with amazing results as all the different traits manifest. For many growers, hybridizing and creating new cultivars is the most enjoyable aspect to growing peppers. And we can definitely see why :)