Starting the seeds or pits from fruits you buy in the grocery store rarely produces trees that bear edible fruit, but they do produce interesting houseplants. Tropical fruit seeds may develop into unusual plants that are sure to be the topic of conversation when guests visit. Some seeds require cold stratification (exposure to cold temperatures for an extended period) before germinating, but many can be started right away.
Cold stratify seeds from trees in temperate climates, like apples, peaches and plums, for eight to 12 weeks to break dormancy. First, remove seeds from the fruit and rinse in lukewarm water to remove fruit residue. Allow to dry.
Place seeds in a plastic food storage bag filled with moist peat moss and store in the refrigerator or in an area where temperatures remain between 40 and 45 degrees F. Puncture several holes in the bag to allow air circulation. In colder climates, seeds are exposed to low temperatures through the winter and germinate naturally in the spring when weather warms.
Check the seeds and peat moss periodically for any signs of drying or disease. If seeds are too wet, they may mold or rot, but they do require moisture to keep them from shriveling. Open the bag for a few days to release excess moisture if the moss remains wet or mist with water if it becomes too dry. Sprouts may appear during storage. If seeds sprout early, they can be planted at that time.
Remove from storage (after eight to 12 weeks) and plant in moist seed starter in early spring. As a rule, seeds should be planted three times the depth of the seed. Cover the seed and firm down with your hands to remove air pockets. Keep soil evenly moist until seedlings emerge.
Start seeds from tropical fruits, citrus and others that grow in warm climates in moist seed starter as soon as they are harvested for the best germination. Some seeds have a short germination period and if held too long will not germinate. Seeds in warm areas germinate naturally as soon as the fruit decays and seeds are exposed to soil.
Rinse seed in lukewarm water to remove plant residue or pulp. Allow to dry slightly and plant in moist seed starter.
Cover the pot with plastic wrap to maintain humidity and place in a warm location. Keeping the soil warm speeds germination. The top of a water heater or other appliance that provides steady low heat is ideal.
Remove plastic and move to sunny location as soon as sprouts appear. Keep soil moist until seedlings show vigorous growth. Water when soil dries to the touch.