Answer: The oranges we can buy at the grocery store are hybrid varieties so seeds taken from them may not be viable. Most orange trees grown for fruit production are grafted rather than grown from seed, this assures a good quality of fruit on the tree. The Sunkist company has a good explanation of the process at their web site at
It takes many years for a seedling orange tree to mature sufficiently to bear fruit, say six or seven years under good conditions.
To start the seed, use fresh seed and plant it in a seed starter potting mix such as one half milled spagnum peat moss and one half clean coarse sand or perlite. Keep slightly damp like a wrung out sponge. Cover the pot with plastic wrap and set it in a bright location but out of direct sun. The room temperature should be about 70 degrees. As soon as germination occurs (about a month to six weeks) remove the plastic and provide bright light.
If you want to try to grow oranges, the best way is probably to purchase a citrus tree that is suited to container growing such as Calamondin orange. It should be grafted onto a dwarfing rootstock such as "Flying Dragon" so it will remain at a size that can be grown successfully in a container. (Most orange tree varieties are far too large for indoor growing.)
Here is more information about container citrus that you may find helpful.
Good luck with your project!
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