To determine if your Plumeria seedlings need more or less water, observe the moisture level of the growing medium. Stick your finger into the soil to a depth of about 1 inch (2.5 cm). If it feels dry, it’s time to water the seedlings. If it feels slightly moist, you can wait a day or two before checking again. Avoid allowing the soil to become waterlogged, as this can lead to root rot. On the other hand, do not let the soil dry out completely between waterings. Consistent but careful watering ensures that Plumeria seedlings receive the right amount of moisture for healthy growth.