Start the fresh starfruit seeds in damp peat moss. Germination may occur in 1 week or as long as 3 months (depending on the species). How to Plant a Starfruit Tree. This very unique fruit is also a kid favorite, but the tree will also look very impressive in your garden! The starfruit is a fast grower and performs best in USDA growing zones 9-11 outdoors and 4-11 on the patio (potted tree) in full sun. Step 2. They must be harvested from the fruit when they are plump and mature, then planted within a few days. These trees are propagated via seed or by grafting.That said, seed from this particular fruit is only viable for a short period of time, mere days at most, so use the freshest seeds available to increase the chances of germination. Growing a star fruit tree (carambola) from seed. Germination usually occurs in May or during the spring season. Gently water your seeds to keep moist, not soaking wet. Growing a New Starfruit Tree from Seeds . Place the seed on the surface of the soil. Only large and thick seeds are suitable for propagation. Starfruit is that star shaped fruit you've probably seen a few times at your local grocery store. Heat & humidity is critical for germination. Carefully cut the fruit, take care not to cut the seeds. Remove all of the seeds. Starfruit seeds lose their viability quickly. Start by buying a few ripe star fruits from the grocery store. Growing a star fruit tree (carambola) from seed 1. 4. Growing Starfruit Tree from Seeds. Your seeds will naturally stratify during the cold winter. Starfruit Seeds are seeds used to farm for Starfruit.Unlike other seeds, these cannot be bought from the Seeds Merchant and are instead only obtainable by harvesting a starfruit on the Buffalkor Island or Wizard Island, the drop chance is 4% or 1/25.Starfruit seeds are the only seeds that cannot give an extra seed when harvesting. Keep your seedlings indoors for 2-3 months before transplanting outdoors in the spring (May to June). The Starfruit tree is a slow-growing tropical fruit tree native to the Philippines, Indonesia, India, Malaysia and Vietnam. If your seeds require pretreatment: you should plant your seeds outdoors before the ground freezes in your area (late September to early November). The Starfruit tree blooms red purple flowers year-round under tropical weather conditions. Spread a very thin layer of medium over the seed, then tamp it down lightly to increase contact. Eat some of the fruit (the fun part) to see if it’s sweet and worth planting. Location: Choose a location where your Once your seeds germinate, move each seed into its own container under the growing lights and on the heat mat. Asian in origin, this juicy, yellow fruit can go from very sour to very sweet, depending on when you eat it! Keep your growing lights on 14 hours per day. Starfruit trees mature to a height of 20-35 feet tall and 20-25 feet wide. They can be purchased at the Oasis and occasionally from the Traveling Cart.One seed can be obtained from Gunther at the Museum after donating 15 items. Place your seeds 1 inch to 1 ½ inches below the soil surface. Place the seed container on a heat mat under growing light (s). How to grow a star fruit tree from seed Do not wait for the year to plant the seeds. We pledge that we do not knowingly buy, sell or trade genetically engineered seeds or plants. How to Grow a Star Fruit From Seed Step 1. Place the seed container on a heat mat under growing light(s). Produce tremendous success in tropical areas, which flourish well in the cold-free areas of the US Department of Agriculture’s hardiness zone 9b -11.