During early summer, I’ve taken several ripe Vaccinium corymbosum blueberries and kept them frozen for 6 months. During that time, they should become stratified enough to complete their dormancy. Without stratification period in the freezer, seeds would not become viable and would fail to germinate.
When blueberries thawed, I placed them into strainer and broke them into small pieces with my fingers. At the same time I was pouring cold tap water through the strainer, to clean the seeds and take out larger pieces of fruit without the seeds. I placed the seeds into paper towel and placed it on a drafty windowsill to dry. When dried, I started preparing peat moss for them to start germinating. The seeds are small, so I decided to use blender and shred the larger particles into small pieces.
Blueberries need a lot of light, moisture and slightly acidic soil. They can germinate slowly, so I had to make sure to prevent mold from destroying the young seedlings. I used microwave and sterilized peat moss, before I planted the seeds. I also tried fermenting several seeds for 2 days and started germinating them in wet paper towel.
One month after I started, I’ve already had mold issues in both, peat and paper towel. After that I placed peat out of it’s originally planned sealed plastic bag, so It could dry out a bit. It dried out… a lot. I then noticed peat is way too compacted, so I used a toothpick to make it at least a bit softer and aerated. After a month, there were no signs of germination and after all the issues, I almost gave up. Before throwing everything into compost bin, I finally saw one tiny seedling starting to break free. After only a couple of days, more seedlings appeared and at the same time, I noticed that seeds in the paper towel also started sprouting. Despite the fact that seeds were fresh and stratified, they took more than a month to finally start germinating.
One month after seedlings first appeared, I decided to give them more light. They immediately started growing faster and started changing color to darker green, with more red coloring in new leaves. I used very small containers so they needed watering every two days in intense light. Before, when I placed them into completely shaded location, they only needed watering every couple of weeks.
Placing the seeds into small germinating trays soon became an issue. As seedlings started to grow, they were more and more susceptible to drought. I placed some into well fertilized peat and they died instantly, as I expected they would. Remaining seedlings were placed in clumps into pure peat on May 2nd when sun isn’t strong enough to kill them, but can fasten up their growth.