Growing Plumeria from Seeds Growing Plumeria from Seeds: Fill small plastic trays or pots with potting soil. We use the seed greenhouses you can buy at any garden store Place the seed into the soil, leaving the wing sticking up. Press the soil around the seed to keep it in place Place the pot or seed tray in a sunny location Wait 3 weeks and keep the soil moist- you should start to see signs of germination!