NordMax21® Royal Empress Tree

NordMax21® is a fast-growing Paulownia hybrid selected by WeGrow for tree production in colder regions. The developer describes broad cold tolerance that varies with plant age, management and weather, while a nursery listing gives a mature garden size of about 40–50 ft tall by 30–40 ft wide and USDA Zones 5–11. ### Site and growth Use [WeGrow’s variety information](https://wegrow-croptec.com/en/order-kiri-trees/kiri-varieties/) for selection details; its cold-temperature figure is not a USDA-zone conversion. The [nursery profile](https://www.brighterblooms.com/products/nordmax21-royal-empress-tree) supports the existing zone and size ranges and lists full sun to partial shade. Plan for a large tree and check local space and utility requirements before choosing a site. ### Establishment Plant in a sunny or partly shaded position with room for the eventual crown. Water deeply during establishment and through dry periods, especially while the root system develops; avoid persistently waterlogged ground. ## Maintenance Inspect for crossing or damaged branches and prune selectively while young to develop the desired structure. Follow local guidance for planting and management of fast-growing trees.