How to Sprout Bonsai Seeds
- 1). Fill a jar or bowl with room temperature water. Drop the seeds into the water and allow them to soak for five to six hours. Dispose of any that float to the top, as these are not viable and will not sprout.
- 2). Place the soaked seeds in a plastic bag. Store the bag at room temperature for four days in an area that does not receive high light or direct sunlight.
- 3). Store the bag in a refrigerator at a temperature around 40 F. Start the bag in a bottom shelf or drawer, where it is warmer, and then move the bag up a shelf or drawer over the course of the next two weeks, until it hits the top shelf, where it is coldest, two weeks after you put it in the fridge.
- 4). Move the bag in reverse over the next two weeks so it ends up back down in the warmest place in the refrigerator. This process of gradually cooling and warming the seeds mimics the freeze/thaw cycle of outdoor wintering, where seeds stay dormant until they have cooled and then warmed again. This tricks the seeds into thinking it is spring and time to sprout.
- 5). Fill a small planting pot or seed tray halfway with equal parts organic compost and fine sand. Gently compress the mixture and then sprinkle the seeds over the surface, leaving at least an inch between all seeds. You can use separate trays or pots if desired.
- 6). Cover the seeds with a layer of compost that measures two times the thickness of the seed. Cover the compost layer with a thin layer of sand. Water using a gentle spray or flow so that you don't disturb the seeds. Add water until the excess flows from the drainage holes.
- 7). Store the seeds in an area of filtered sunlight at temperatures between 50 and 60 F. If you are using tropical tree seeds for your bonsai, store them between 65 and 75 F.
- 8). Gently water the seeds whenever the soil dries out a little, until the excess runs out of the drainage holes. You must keep the seeds moist to encourage them to sprout. For most species, sprouts should appear within a month of planting.
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