What is stratification?
In nature, seeds require certain conditions in order to germinate. Seed stratification is the process whereby seed dormancy is broken in order to promote this germination. In order for the stratification of seeds to be successful, it is necessary to mimic the exact conditions that they require when breaking dormancy in nature.
Do all Plantui seeds require stratification?
No. Only seeds that are not native to our tropical climate will need to undergo stratification. A great example would be the Sweet Blond which requires temperatures to drop, then rise in order to break its dormancy - this mimics coming out of the cooler winter season. If you are growing the Sweet Blond in our sunny Singapore, it will require cold stratification in order to germinate.
How do I administer cold stratification?
We will walk you through the simple process, but all you will need is a refrigerator!
Remove the capsules from the pack as you normally would.
If you are growing small seeds, check behind the peel-off sticker, check around the rockwool, and lastly check between the sticker and rockwool itself to see if there are seeds stuck. If they are, simply help push the seeds into the middle so they can grow well.
If you are an ultra perfectionist, then try to make sure the seeds are all in contact with the rockwool. This is so that they all get into contact with the water!
Tilt the capsules slightly (so their seeds don't fall out) and slowly wet the rockwool under a tap. The rockwool is fully wet when it changes to a darker colour. You should see the top of the rockwool turn fully dark too.
Place the capsules in a ziplock bag and place them in the lower section of your refrigerator. You will be leaving them in the refrigerator for about 24h.
After 24h, take them out of the refrigerator and plant them in your Plantui as you normally would.
Depending on the variety of seed you are growing, you should see the seedlings start to sprout within a few days to a few weeks! For this example with the coriander, the fastest seedlings started sprouting on day 3, and by day 8 all of them had sprouted.
Now you know the secret of growing non-native seeds ;) Happy growing!