Following on from the planting up of some acorns in October 2020, they are already starting to develop, even though you cannot see anything above the soil in the pot, a lot has been happening below ground in and out of the pots. So just because most of your bonsai trees will have gone dormant for the above part of the pots over winter, be aware that the roots are still active and functioning in the pots albeit at a slower rate depending on how you are over wintering them.
Tree roots will grow in the right conditions if they have water, oxygen and the right temperature. As these were in a cold green house on a bench on a plastic tray it appears to have so far been the right conditions to start growing roots and for the acorns to start germinating.
The roots have started to come out the bottom of the pots and root hairs can be seen on these fleshy roots. I have not been watering them too much, once a week just to keep the soil moist but perhaps I need to up my watering…
I have also put a pumice layer now in the plastic trays to help protect the emerging roots from the holes in the bottom of the pots to stop them freezing as the temperatures have suddenly dropped to below freezing currently. I cannot wait till they start hopefully to develop a shoot but until then it gives me a lot of opportunity to look at the roots close up.