Plant library · Ornamental & Flowering Trees
Paulownia tomentosa
Empress tree is a fast-growing shade tree that reaches about 40 feet tall and 30 feet wide, with oversized leaves and fragrant purple flowers from mid to late spring. Its scale and rapid growth make it a major long-term element rather than a filler tree. Reserve it for a large, open part of the plan where its canopy can become a deliberate feature and where future shade will not overtake smaller sun-loving plantings.
Place Paulownia tomentosa well back from the house, patios, utility lines, fences, and regularly used garden rooms. A rounded, spreading canopy creates dense shade beneath it, so keep vegetable beds, sunny borders, and low plantings that need direct sun beyond the eventual canopy edge. Use it only where a large tree can stand apart from paths and seating areas, with clear circulation around the trunk and room to manage fallen capsules and new shoots.[1]
Space trees 30 feet apart, center to center. That interval matches its roughly 30-foot mature width, but it leaves little separation once branches fill out; give it additional open space when planting near other trees, buildings, or property edges. In a scaled plan, draw a 30-foot-wide canopy circle and keep paths, beds, and outdoor living areas outside that zone rather than treating the trunk as the tree’s full footprint.
Give empress tree a full-sun position and moderate water. It adapts to a range of soils, with best growth in moist, well-drained ground; avoid making it the focal tree for a persistently waterlogged site. Because it develops quickly, choose its permanent position before nearby beds, irrigation lines, and garden structures are established around it.[1][2]
The purple, fragrant flower display arrives in mid to late spring, before the large summer canopy takes over the space. Flower buds are formed on older wood and can be damaged by severe winter cold or late frost, so bloom may be inconsistent in exposed cold pockets. Woody seed capsules follow and open in fall, extending the tree’s seasonal presence beyond flowering.[1][2]
This species is invasive and is not a sound choice for most home landscapes. It self-seeds readily, and cut trees can resprout from roots some distance from the original trunk, making removal difficult. Its weak wood, messy habit, and fast expansion add maintenance and safety considerations, especially beside driveways, play areas, roofs, and neighboring properties. Do not use it on a small lot or where seed spread beyond the planting area would be a concern.[1][2]
Editorial content updated 2026-07-20.