To start a mimosa, buy a potted nursery plant, if they’re available, or start it from seed yourself. Soak the seeds in water overnight. Plant them outdoors when daytime temperatures are at least 65 degrees or sow them indoors in a light potting mix.Click to see full answer. In this regard, how do you start a mimosa tree from seed? Method #1 Open the seed pod which houses several seeds. Separate and place in a folded wet paper towel. Place in a dark cool place. In a few days the seeds will begin to open up with sprouts. Plant in starting soil about 1/2 inch deep, and place in sunny window or outdoors if the weather is warm. Also, how do you plant a mimosa tree? When planting a mimosa tree, keep it at least 10 to 20 feet away from a house or structure. Mimosa trees will grow in conditions from full sun to partial shade. The soil should be high in acidity. A pH level of 4.6 to 5 is ideal. Also Know, how long does it take for a mimosa seed to sprout? Provide plenty of sunlight. In ideal conditions with temperatures around 70ºF (21ºC), the seeds may germinate in under a week. In less ideal conditions, or if you didn’t soak the seeds, this may take two to four weeks.How do you prepare tree seeds for planting?Cover the seeds with a fine layer of sand to a depth about the thickness of the seed. After planting the seeds, gently water them and keep them moist but not wet. Maintaining high moisture and relative humidity is critical to germinating seeds. You can increase the humidity by enclosing the seed tray in a plastic tent.