Purchase a pomelo and slice it open to retrieve the seeds. Pomelos are most commonly found in Florida, California, Arizona and Texas – the “warm” states that pomelo trees thrive in.
Wash the seeds and let them dry. Plant them as soon as possible to prevent the seeds from drying out.
Fill your large container three-quarters full with potting soil. It may seem silly to plant a few seeds in such a large container, but your seedlings will need time to grow, and the fewer times you can reduce transplanting, which creates “root shock,” the stronger your pomelo tree will be.
Sprinkle the top of the soil with water so that it is wet and spongy but not soaked.
Scatter between eight and 12 seeds across the top of the soil, about 1 inch apart. The size of the seeds in the pomelo fruit may vary greatly – this is normal – so choose a combination of large and small seeds to plant in the container.
Cover the seeds with about 1/4 inch of potting soil. Cover the soil with a light layer of mulch to help keep the soil moist.
Water the soil until it is very damp. Do not let the water form puddles.
Cover the container with plastic wrap. Put the container in a location where it will soak up sunlight most of the day.
Keep the plastic wrap over the seeds until they germinate, which should be in about 10 to 14 days.
Fertilize the seedling regularly with a water-soluble fertilizer designed for citrus trees.
Continue to water the seedling and, if necessary, prop it upright with a craft stick and string if it begins to sag. At this point, germinating trees from seeds becomes more art than science. As you must monitor it carefully, keep the soil moist at all times and prune any gangly growth.
Transplant some seedlings to another pot if you find that they are “fighting” for space in the container. Pomelo trees need ample room to grow and should not be crowded. But your primary tree should be well-suited to its container for several years, until it is big and strong enough to be transplanted in your garden.