Paulownias – including P. tomentosa, P. fortunei and P. kawakamii – are fast growers that can reach up to 26m if left unpruned. They are impressive, beautiful trees with scented flowers in late spring, and in their native China they are prized for their wood. In western gardens, they are often coppiced to encourage the giant leaves that go with the post-pruning growth spurt.
Planting Paulownia makes an exotic impact in a border, as a backdrop to delicate summer perennials or combined with other bold foliage plants for a dramatic effect.
Cutting While coppicing is generally best when plants are dormant, paulownias can be left until late in the spring – even May, after flowering. If you plan to coppice a mature tree, check it doesn’t have a tree preservation order, and ask an approved arboriculturist to do the initial pruning.
Tackle the pruning in stages, first removing outer branches with a small pruning saw to get access to the main stems. Cut larger stems using a jump cut to remove cleanly. A jump cut is actually three cuts. With the first two – upwards halfway from beneath, then downwards – remove the bulk of the stem, except for a short stub; the third cut removes this remaining stub.
Work your way down to the base of the plant, leaving a clean, smooth stool no more than 10cm above the ground. Mulch straight after coppicing and use a liquid foliar feed through the first growing season. By season’s end it will have produced a lush set of new leaves. The coppiced Paulownia grows as broad as it is tall, so allow 3-4m for expansion after the first cutting. Read our piece on why you should coppice.
Spring: after flowering
Before cutting, this Paulownia kawakamii is 3m wide and 4m high. Previous coppicing has increased the size of the leaves, encouraging the branches to grow outwards, in search of light.
The final stage of coppicing looks brutal, but it’s vital to leave a clean, smooth surface. Damaged wood makes it easier for disease and rot to creep into the stool.
Summer: outsized foliage
After one season, the new growth is abundant. Individual leaves are huge, some as much as 24cm in diameter.