Is there a way to restore/heal fallen Royal Thorns?

[N3MES1S]

The only way to resurrect plants is with sacrifice spell or the drain life demonologist hability. U can sacrifice inquisitors, or another level 2-3 troop and u gain 2-3 royal thorns. Then u resurrect the sacrificed troop. If u seen u are going to lose more r thorns than the ammount of gained with sacrifice, cast invisibility spell on em. And remember r thorns are level 4 units, u can cast fear on any enemy level 1-4 (if u have level 3 fear or 1-3 level 2) and worry only about level 4-5 enemy stacks. If u can, use demonologists. Demonologists + sacrifice spell, too hard u lose any royal thorn.