The paulownia tree is a fast-growing tree that can grow to between 12 and 15 feet tall in the first year of growth. Even though the paulownia tree is an attractive ornamental producing masses of showy, fragrant blossoms, it is mostly prized for its highly useful timber. Regarded as the "King of Hardwoods" by Donald Graves and Jeffrey Stringer of the University of Kentucky, in the United States paulownias are becoming widely planted on a commercial basis. Growing paulownia from seed requires careful preparation and a generous amount of land.
Preparing the Planting Bed
Prepare the planting bed in either late winter or early spring. To do this, cultivate the soil in the planting bed using a spade or a rototiller to save time.
Apply a soil fumigant to the soil in the planting bed to destroy weeds, nematodes and any fungus. You can contact your agricultural extension office for recommendations on which fumigant you should use.
Incorporate a fungicide into the top 2 to 4 inches of soil in the planting bed to further ensure no fungus will destroy the paulownia seeds. Your agricultural extension office can also recommend an appropriate fungicide.
Measure out approximately 1 to 2 cups of a 14-14-14 granular fertilizer for every 1 square yard of planting bed. Broadcast it out across the topsoil then mix it into the soil thoroughly using either a rototiller or a spade. Smooth and level out the entire planting bed using a metal rake.
Planting Paulownia Seeds
Moisten the planting bed before planting the paulownia seeds at the rate of 12 to 15 seeds for every square yard. Avoid covering the seeds. Mulch the planting bed with a 1 inch layer of straw to retain moisture, which is essential for germination.
Water the seed bed with a fine mist of water as often as needed to keep it moist. Germination of paulownia seeds can begin in two to three weeks.
Remove the straw when seedlings are 2 inches tall. Cut off at the soil line the least hardy seedlings to leave 10 seedlings to every square yard.
Transplant the paulownia saplings into their permanent location when they are about 3 to 4 inches tall.
Select a sun-filled planting area that has all vegetation, such as weeds, removed and has been cultivated to a depth of about 16 to 18 inches.
Dig holes for each paulownia tree that are wide enough and deep enough to accommodate its root system. Each hole should be no closer than 20 feet apart.
Dig up a paulownia tree making sure to include as much of the roots as possible. Plant the tree into a previously dug hole and water thoroughly.
Water each paulownia once or twice every week during the summer growing season for the first two years after transplanting. Depending on conditions, the paulownia trees may be ready for harvesting in approximately five to 10 years.