Where you live is important because conditions can very. Do you use heat or lights or are they always outside. Some products for a loose soil are not available everywhere even here. So depending on where you live is what you use. Needs large particles so water can run through. Are you using the same soil on your seedlings as you bigger trees?
I killed my seedling slowly because I did not give them steady moisture. Seedlings are different then older tree's.
Mine are still in the house. A lot of us here in the States are getting odd weather. All last week it was 80f/26c. Today we have snow showers even my house is cooler with no sun shinning, I have not watered. I stick my finger into the soil about an inch or two. Then I know if it is wet or compacted. I use the Gritty mix but it was to dry for my area, so I added coir powder.
How are the stems and caudex? are they firm or changed color?
