F1 Generation: The first generation of hybrid seeds is referred to as "F1," where "F" stands for "filial," meaning offspring. F1 hybrids usually exhibit what’s known as "hybrid vigor," meaning they often grow better or stronger than either of the parent plants. Germination Time: Apple gourd seeds typically take about 7-14 days to germinate under ideal conditions, depending on temperature and moisture levels. After germination, you will start to see small seedlings sprouting from the soil.