Cannabis Seeds Float or Sink Test
The float or sink test was once a popular way to test if a cannabis seed has expired or not. Legend has it that the seeds that sink straight away in water are good, and the seeds that float on top of the water are bad. But this test is actually a complete myth and should never be used to test whether a seed is still viable. Some seeds will naturally sink whilst others float.
However, whilst the float or sink test is completely inaccurate there is a little bit of sense too it.
The logic behind the test
When a fresh cannabis seed is harvested it will contain more water than an older seed that has spent time in storage around pouches of silica gel. Due to a fresh seed containing more water it will be heavier and quickly sink when placed in water.
An old expired seed could of completely dried up inside leaving the seed as nothing but an empty shell. This would then have air inside the seed causing it to float on water.
Conclusion
For these two reasons above, the float or sink test for cannabis seeds does make a bit of sense.
However, it is well known among growers that floating seeds still germinate and are able to grow into perfectly healthy plants. Many growers will notice that seeds that float on water will often sink after 24 hours when the seed begins to germinate and crack open.
