Some seeds, before they will germinate,
need a cold period to break dormancy . Below are a few of the directions
listed on the labels for some of those seeds:
Teucrium flavum - Lightly cover seeds and use 70F,
germination in 1-2 weeks, if no germination in 4 weeks put in the refrigerator
for three weeks than move back to 70F.
If the directions for your seeds read something
like the above example, these seeds many times will germinate without the
cold period and should be sown at the recommended temperatures first. If
little or no germination, move the pots to a colder location (32-39F) for
the recommended period. If sown into a pot - the pot can be put into a
large plastic ziplock bag and sealed up and put in the back of a fridge or
if its still cool, put outside. If put outside use a sheltered location outside,
away from direct exposure to bright sunlight. It is important not to let
the soil/seed medium dry out during the cooling period. Also the soil/medium
should not be soaking wet - just damp. By putting the pots in a plastic bag
you will keep the medium from drying up.
Alchemilla mollis - Sow at 65ºF for 3 weeks
then move to Fridge for 3 weeks, return to 65ºF where germination will
occur in two weeks. Light helps germination so surface sow.
If the directions are like the above example
the seeds need a warm-moist period first and then a cold-moist period before
they will germinate. You can do this a few different ways, sow in a pot as
normal and seal up in plastic bag and leave at room temperature for the recommenced
period then move the pot to the fridge or outside.
If the seeds are not two small, you can sow the seeds into a small plastic
baggy or container with one tablespoon of moist (not soaking wet) seed medium/soil.
Keep the container with the seeds and medium at room temps for the recommenced
period then move to the fridge for the recommenced cooling period. This will
save you room. Keep an eye on the seeds because sometimes they will begin
to germinate while in the container or bag and at that time should be sown
into a pot. Gently scatter the soil-seed mix over the soil in a pot and gently
water down with a few hands full of water so that the seeds are in good contact
with the soil in the pot. In the above example the seeds need light - so
leave as is, otherwise sprinkle a thin layer of soil-medium over the top
of the seeds and water some more.
Another way to sow the seeds that need a cold
period is to sow them in pots or trays and place them in a sheltered location
outside in the fall or winter. If the seeds need a warm-moist period first,
they will need to be sown in late summer or early fall - or you can sow them
inside in the winter and then move them outside after the warm period is
done (Make sure that it will be cool enough outside, long enough to fulfill
the seeds needs). One can also sow seeds in the fall and bring them inside
again in late winter for early germination. This will give a few weeks of
growth and larger plants when it is time to plant outside. If you have a
cold window sill, it can be used for the cold period too - make sure that
it stays below 42 degrees Fahrenheit for most of the day. If you use a cool
window sill in the winter you may need to increase the cooling period by
double, keep an eye for germinating seeds. ( Most seedlings of plants that
need a cold-moist chilling period can handle cold temps as small plants,
so do not move the pots until a good percent of the seeds have germinated).
Keep soil/medium moist at all times and prevent drying by putting in a plastic
For most seeds that need a cold-moist period,
the cooling period does not need to be below freezing, with 34-39 degrees
Fahrenheit giving the best results. But for most of the seeds in RANUNCULACEAE
plus a few others, the cooling period needs to be colder, with 15-25 degrees
Fahrenheit working well. The seeds include those plants in: Aconitum, Anemone,
Caltha, Hepatica, Ranunculus, Trollius.
If you are not going to sow your seeds right
away, they should be stored in a cool dry location, most seeds can be stored
for a few years in the fridge. Seeds from tropical plants should be stored
warmer 55-70 degrees Fahrenheit. Avoid exposing stored seeds to direct sun
light and/or high humidity/water.