The dead of winter is when pepper germination begins, particularly for peppers at the habanero stage of SHU (Scoville heat units) or higher. Super hots just don’t germinate well at all. It is thought that germination is hindered by capsaicin. (read this helpful research article) There are a variety of methods to induce greater germination explored in all my gardening groups, everything from soaking in water for 2 days to using hydrogen peroxide to soaking in mild acids and finally treatment with a growth hormone. Sometimes a combination of several methods is used.
Please note that all images are from initial recording and do not include the germinated seeds from the final 4 days when I was away.
I had always had good results with tossing dry seeds into a paper towel and waiting until I started to sprout super hots. I wanted to test how these methods work for myself. I had a bunch of ghost peppers and others that simply would not germinate. I set up a not overly scientific test with 10 habanero seeds per method- 24-hour soak in water, 24-hour soak in 1% hydrogen peroxide, physical scarification (nicked with an exacto), 24-hour soak in 100mg aspirin in 5ml water, and a control where I did nothing. These seeds were then divided- half of each 10 seed lot went into damp starting soil and the other half onto a damp paper towel in a baggie.
Shortly after I started this experiment I received some Red Scotch Bonnets and wanted to use those for the Khristmas Kratky grow contest for one of my pepper groups. I soaked 3 seeds in 1% hydrogen peroxide for 24 hours. At the same time, I wanted to see how Carolina Reaper seeds responded, so I dropped 3 seeds into another vial with the same 1% solution. 5 days into the experiment I received some seeds for Yellow Jelly Bean chilis, so I decided to test a 48-hour peroxide solution after a soapy water rinse.
I started another round with a soapy water rinse, then 48-hour soaks of both water and 1% hydrogen peroxide, and then half were given a brief shake in an aspirin solution. There were another 10 seeds. All were then put onto paper towels and plastic baggies. I mention these other attempts with purpose.
At the 6-day mark, the first seed germinated- in the 24-hour water soak using the paper towel method. On the 8-day mark one of the discolored scarified (knife nicked) seeds germinated. I thought this seed had started to rot. On the tenth day, a peroxide seed germinated. On the 11th day, a second seed from the water batch germinated. On the 14th a control seed germinated. As of this writing, none of the seeds in soil have germinated.
Let’s discuss the other seeds. Two out of three Carolina Reapers germinated after 9 days. The third seed looks good and may still germinate. My Scotch Bonnet seeds germinated after 12 days. One of the four Yellow Jelly Beans germinated after a mere 6 days, one looks discolored and the other 2 look good.
My 24-hour soak results suggest that any sort of scarification method, other than aspirin, will help germination. Water seems to work as well as peroxide. Even with that, my results with other super hot seeds seem to contradict that finding. Of course, this means that I’ll need to attempt more tests. The 48-hours soak, without aspirin, seems to be more promising. More seeds have germinated than the 24-hour soak. What does seem to be true of all of these tests is that these habanero seeds are not that viable, especially when we consider the generally low germination rate for hot peppers- that the Reapers and Bonnets had a 66% to 100% germination rate as of this writing. That only 1 out of 10 each has germinated is ridiculously low.
So these results are inconclusive. I’ll restart with seeds that I know are viable- gochu or macho peppers. Macho might be a better fit as they are substantially hotter than gochu, but aren’t as hot as habaneros. I suggest these 2 not due to heat but because I know that these seeds are very viable. I’ve had more than 80% germination with both, and closer to 100% with the Macho. Also I really love the tiny compact Macho plants. I will do smaller amounts with some super hots- Trinidad Scorpion peppers, or Bhut Jolokia. As these are both super hots I intend to grow this year it would be a useful test.
Obviously, I’m disappointed with these results. It is known that soaking helps, peroxide is thought to assist in softening the seed hull and to be safe to the seed itself as it breaks down into water and oxygen. My understanding is that gibberellic acid(GA) speeds germination of pepper seeds greatly. So when that arrives I’ll add a round using GA to my tests.
Update. I spent 4 days away from home for the holidays. When I returned I found the following changes- all of the original test seeds from the water and peroxide soaks germinated. The control seeds also all sprouted. I had 3 seeds germinated in starting soil- water, peroxide, and control. Since removal from the hot box, another water-soaked seed germinated. The rinse and soak tests also had germination- all the 48-hour soak without aspirin germinated. Those with aspirin did not germinate. All 3 Carolina Reaper and Scotch Bonnets soaked in peroxide germinated. 2 of the 3 Khang Starr Lemon StarrBurst soaked in peroxide germinated and another not soaked, germinated after more than a month passed.
I’m still deeming this test inconclusive, it seems that my hab seeds weren’t as bad as maybe I had thought, but it shows nothing in terms of motivating germination. All this has led me to believe is that soaking speeds germination no matter the media- except aspirin. In my further testing, I will not be using aspirin