Guava seeds will germinate as soon as two weeks after planting, but they may take as long as eight weeks. The trees can also be grown from root cuttings. Seedlings are fast growing, and they can be set out in the field after one or two years.
Growing tropical guava in a greenhouse or on a protected porch from seed is a fun project to try. In tropical climates, guava trees grow up to 12 to 14 feet tall, but kept in a container, they stay small enough for a covered porch or small greenhouse. Commercial growers use grafted trees to get specific fruit characteristics, but in the home garden, growing guavas from seed is a simple and fun way to add to the garden landscape. Grow guava outdoors in U.S. Department of Agriculture plant hardiness zones 9a through 10b. In the chillier zone 8 areas of the region, keep your guava tree in a pot on a sunny, covered porch in winter
Guava Plants: How To Grow And Care For Guava Fruit Trees. Guava fruit trees (Psidium guajava) are not a common sight in North America and need a decidedly tropical habitat. In the United States, they are found in Hawaii, the Virgin Islands, Florida and a few sheltered areas in California and Texas