I bought a "dwarf" mulberry not grafted--one of those everbearing dwarf trees I figured was dwarfed only because it was potted. When I asked the supplier if it was a genetic dwarf, I was told it was tissue cultured. Okay, and? My question is if there is some special way to culture a tree to dwarf it? I haven't heard of anything, but there's lots I haven't heard of. Thanks.