The mimosa tree (Albizia julibrissin) is also known as the silky acacia and the silk tree. It is a native flowering tree to China. Mimosa trees can grow to 40 feet tall and are hardy in the USDA Zones 6 to 10. They are easily recognized by their fine, airy, fern-like foliage and brightly colored, salmon-pink colored plume-shaped flowers. With a little careful preparation, growing mimosa trees by seeds is a relatively simple procedure.
Mix together approximately 1 to 1 1/2 cups of sphagnum moss and enough water to dampen the sphagnum moss so it feels moist to the touch but not soggy wet.
Place the dampened sphagnum moss into a lidded plastic container. Set the mimosa tree seeds into the sphagnum moss. Set the lid on the container and give it a gentle shake to distribute the mimosa tree seeds into the sphagnum moss.
Place the lidded container into your refrigerator for three months. Open the lidded container every other day to make sure the sphagnum moss is remaining moist. Spritz the sphagnum moss with water as needed to keep it moist.
Remove the mimosa tree seeds from the cold storage location after the three months has passed and remove a small section of the seed coat on each of the mimosa tree seeds. To do this, hold the mimosa tree seed with a pair of tweezers and use a nail file, scissors or a small knife and scratch off a piece of the seed coat.
Place the mimosa tree seeds into a bowl. Pour approximately 4 cups of water into a pan and heat the water to a temperature of just below the boiling point, approximately 190 degrees Farenheit.
Pour the near-boiling water over the mimosa tree seeds. Leave the mimosa tree seeds soaking in the water for no more than 12 hours.
Sterilize the plastic pots before using. Bathe the 3- or 4-inch plastic pots in a solution of one part bleach mixed with 10 parts water. Rinse the pots in tepid water and set them upside down to air dry. Pour a good quality seed starting compost into each pot and pack the soil down firmly.
Transfer the pots to the warmest location within your home. Try and provide a temperature range of between 65 and 70 degrees Farenheit with a good source of light daily, about six to eight hours, but not direct sunshine. Germination will begin in approximately two to four weeks, depending on growing conditions. Once the mimosa tree seedlings are approximately 2 1/2 to 3 inches tall, you can pot them up into larger containers, or plant them in the ground if weather permits.