"Dave Poole" wrote in message
...

The two main reasons for soaking seeds a

1) To rinse out soluble enzymes within the seed coat which act as
germination inhibitors.

2) To soften the hard outer seed coat allowing moisture penetration
for faster germination.

For some seeds, an overnight soak in tepid water is enough. For
others several to many days soaking and rinsing may be necessary to
break the dormancy.

Someone has mentioned Musa - these are always tricky since unless the
seed is very fresh, dormancy is severe and difficult to break. They
need at least 5 days soaking in warm water and daily rinsing, followed
by sowing in temperatures of at least 30C and preferably 35 - 38C.
Closely related Ensete and Musella are easier, they need a similar
soaking, but will germinate at around 25C.

Cannas are another 'hard' seed that are often tried with varying
degrees of success. In these, the seed coat comprises of several
veneer-like layers which need to be bridged before the seed can
germinate. The seeds are placed in a container and covered with very
hot water, just off the boil. Within seconds the seed coat layers
crack audibly and an equal amount of cold water is added. The seeds
are left to soak overnight in a warm place and sown the following day.
Quite often, a proportion of the seed will have germinated within
hours.

Dave Poole
Torquay, Coastal South Devon UK
Winter min -2°C. Summer max 34°C.
Growing season: March - November

Twos me what mentioned Musa.
Grow them every year in a heated propagator and have about a 10% germination
success.
However, I now know not to follow the instructions on the packet and adopt
the methods you have all mentioned.
I have long suspected that the seed is far from fresh so this year I have
ordered seed from three different suppliers and I will try to be as
scientific as possible.
Incidentally last year I gave up on the seeds planted in January after over
6 months and extracted the still dormant seeds and put them all in one big
pot placed on top of a radiator. Bingo about half sprouted within a week but
subsequently withered and died.