Hardy hibiscus (Hibiscus moscheutos) are vigorously growing, herbaceous, perennial flowering shrubs. They are hardy in zones 4 through 9. According to the University of Florida, many varieties of hardy hibiscus are indigenous to Florida and areas in the southeastern United States. The flowers of the hardy hibiscus come in shades of pink, white, lavender and red and can grow 6 to 10 inches in width.
How to Plant Hardy Hibiscus from Seed
Put your hardy hibiscus seeds in to a bowl of warm water and let them soak overnight. Use peat pots, or 4-inch pots and fill them up with potting mix. Make sure to water the soil in each pot so the soil is well dampened down.
Plant the hardy hibiscus seeds by pushing them down into the soil. Cover each seed with no more than a half inch of the potting mix. Spritz the surface of the pots with a light misting of water.
Place the pots into the irrigation tray. Put the tray near a good source of light. Or put the tray under a florescent light at a distance of 5 to 6 inches for 1o to 12 hours a day. Put a half inch of water at a time into the irrigation tray to keep the soil in the pots moist, but don't let them become saturated.
Try and keep the temperature warm, approximately 70 to 75 degrees Fahrenheit. Germination typically begins in approximately 10 to 14 days. Once germination occurs, continue to keep the pots moist, and provide plenty of light as directed in Step 3 above.
When the seedlings have grown to approximately 3 to 4 inches tall, transplant them into larger growing containers.
Transplanting Hardy Hibiscus
Use 1-gallon pots that have been filled with potting mix to transplant your hardy hibiscus seedlings. Scoop out soil in the middle of each 1-gallon pot to the size and depth of each of your planting receptacles.
Gently strike around the rim of each of the 4-inch pots to remove a hardy hibiscus seedling. Cut off the top section of the peat pot to soil level. This helps to prevent moisture loss to the roots.
Place a hardy hibiscus seedling into the gallon pot. Ensure it's sitting level and straight and planted approximately a half-inch higher than the surrounding soil in the pot. Scoop in potting mix around each of the hardy hibiscus seedlings. Pat down the soil to remove any potential air pockets. Water each of the seedlings making sure the soil is well moistened.
Once the hardy hibiscus have grown to approximately 8 to 10 inches tall, transplant them permanently outside, or into barrels or other large growing containers.