Good morning from New Jersey. I am planning to plant some Japanese Maple seeds for growing. I have a few questions since I've found conflicting information across the interwebs. I am considering planting these seeds in August. I will soak the seeds for 24 hours before hand and then plant. I'm considering two methods for planting, both sound interesting to try, and I may try some seeds each way but would appreciate your opinions and advice.

Method 1
Place soaked seeds in peat moss in plastic bags in the refrigerator. Keep these refrigerated through the winter. My understanding is that the seeds will go into a dormancy and when they are pulled out in the spring for planting, they will quickly pop up.

Method 2
Place soaked seeds in peat moss in these containers ( smile.amazon.com/gp/product/B01LX0JBUU/r...A3DSFEQCB8EWN5&psc=1 ). I really like these containers because of the clear plastic domes on the trays. I don't have a greenhouse so having a dome to protect the seedlings from hard rain is appealing. In December, I would move the trays into the garage for dormancy (removing the lids). My understanding is that in the Spring these will take off and possibly be ready for transplant into regular pots by early-summer.

Alternative methods and ideas are welcome.

Another quick question, how do you determine your soil's water saturation level? I feel fairly competent to measure this in the summer, outside but am concerned about watering through the winter dormancy. I am planning to take my deciduous trees to the garage for the winter. The trees will experience freezing level temperatures but won't be exposed to frost. So, I'm anticipating the soil to freeze. How do you go about water plants in this phase?

Thanks for all of your help.

place the seeds in a tray with bonsai substrate. Place the tray outside for winter. Forget about them, and see the seeds germinate in spring. This is what I normally do. But I get seeds fresh from this year, somewhere around october.

What do you mean by bonsai substrate exactly?

bmrscreamr wrote: What do you mean by bonsai substrate exactly?

www.growingbonsai.net/characteristics-of-good-bonsai-substrate/

I thought you started seedlings in a more robust, moisture rich soil and then transplanted them to substrate once they got a bit bigger.

It varies a little. I do this for species that like hot and moist conditions. But for temperate species that require a long cool period, I prefer to use the normal substrate to reduce the risk of rotting.

See for a newb, when you say "normal substrate" I don't know what you mean exactly. I looked at the link you posted earlier but it only gives the basics on what types of materials are good as substrates, but not actual recommendation on mixture. This still didn't tell me much about what exactly you were recommending.

For example, I've watched a few videos about potting bonsai and they discussed mixes and the reasons for their choices in mixtures. But, none of them discussed mixtures for seeds.

Sorry to be a pain but I still don't understand what you mean by bonsai or normal substrate. Thanks for your help.

bmrscreamr wrote: I still don't understand what you mean by bonsai or normal substrate.

Nursery or "loam" soil is organic and not appropriate for long term bonsai, as it is slow to dry and can be easily overwatered (but it is not impossible, it just requires more attention and more work).
Normal bonsai mix (it's an endless argument), is mostly inorganic and drains fast.
Pumice+ Lava + Akadama is a "classical mix" for bonsai.
I always sift my soil components to have the granules between 3mm~6mm and, living in a tropical country, I always use some organic in the mix, like 20% sifted pine bark+charcoal.
BUT...
There is NO definite answer, as it depends on many factors, including pot size and where the bonsai (or sapling, or seedling) is located.