This video shows how I grew hundreds of elderberry plants in 1 1020 tray over the winter. They were grown from seeds & were in the fridge for 6 months! They grew in the tray inside under a Kingbo LED light. I just transferred them to new pots outside in the greenhouse.
Amazon Links:
Kingbo LED grow light - http://amzn.to/2gOB6Sp
1020 Trays - http://amzn.to/2vvueSG
1020 Inserts - http://amzn.to/2gRFCU4
~300 Elderberry plants for about $10.