Elderberry nursery stock

I’m wondering if anyone has experienced or input for propagating elders in an intensive nursery bed. I have a few dozen hardwood cuttings of select cultivars I’d like to multiply. I may use a high tunnel to root cuttings before moving out to go field. We harvested our first bob Gordon berries last year and are excited to expand production.

Any specific ideas on spacing, Timing of transplant,  needs of young plants, shade needs/tolerance etc...? I have 50% shade on a small high tunnel I grow pawpaws in and wondered if they’d be ok sharing space as I often find them together in the wild.

I’ve grown out several cuttings with good success planted directly in the field, but I’m looking for a better way to ensure constant moisture. Summer gets hot and dry and have lost many elderberry hardwood Cutting due to lack of water.