Currently I have my Prunus Yedoensis (染井吉野) and Prunus Serrulata (桜) ready for germination, but there is one trouble, and that is preparing the soil. I wish to make the plants native soil, however I need help with the research on what type of soil it needs so it may stay strong and healthy, and before I turn the plant into a bonsai. Any suggestions on where to look for the type of soil? Thank you! ありがとうございす!
I don't know about any native soil but I do know about the needs of the tree. You will most likely need loam or potting soil, akadama, and some gravel at a ratio of about 3:3:2. There are many cherry trees where I live and I know that they like water retaining soil. Before you get any soil first, wait for more posts as I could be wrong and it will help for you to gain as much knowledge with bonsai.
Although I think Jaimin statements are correct for the most part, I´m leaning to write some remarks, If I may.
First of all, there is no a standard or fix recipe for the "best" soil. However, there are some guidelines that we should follow in order to succeed. For instance, every soil must fulfill three issues, that is: Water retention, drainage and aeration of the roots. So, besides knowing which is the adequate soil for your tree species is one step, the next should be how´s your weather, which leads me to know where are you living. This is because if you live in a hot climate, probably you should increase a little the proportion of the organic material, since this is meant to be the water retention material mainly. Or, if you live in a humid weather, you should probably be prone to increase the ratio of draining material, grit for instance... And so on... As you see, there can not be a standard rule for soils.
For instance, in your case I think a better ratio would be 50% Akadama, 25% grit or lava rock, and 25% of some water retentive organic material (2:1:1 ratio) and starting from there you can adjust your soil to your local weather.
That would be fine for the plants, but I got the impression that it was seed being sown, so the soils suggested I would not use. The compost needs to be much finer for seed.
That is correct Geoff... I fell for it It was talking about seeds.
Well, according to Harry Tomlinson, here is a small guide to properly germinate some seeds:
1- Fill the bottom of a tray with a cultivation soil mix, that is: one part of peat and one part of perlite.
2- Add a thin layer of grit on top of it, so the seeds might remain visible. Then, draw some grooves on this grit layer, this grooves you might want them to be uniformly spaced (groove spacing).
3- Plant the seeds along the grooves. The spacing between the seeds (not the groove´s spacing) might differ according to the species you are planting, since the size of the seed will vary consistently.
4- Cover it all with a new layer of gravel up to once or twice the size of the seed.
5- Water the tray thoroughly and place it outdoors.
Hope, this time I have actually been of some help...