There are three true species of avocados: the West Indian, the Guatemalan and the Mexican. The variety most often sold in commercial markets is the Mexican avocado or a hybrid of two. Avocado can be grown from seed, but don't expect fruit for 10 to 15 years, according to Texas A&M University. However, if time and space are available, avacado is an attractive and tasty evergreen plant to have around.
Rinse off the avocado meat clinging to the seed. Wipe it dry. Place three toothpicks into the seed, evenly opposite each other, about 1 inch up from the bottom (the flat side).
Set the seed over a glass of room-temperature water so that the bottom sits in 1/2 of an inch of water. Place it in a sunny window. Refresh the water if it gets cloudy.
Watch for little white roots to emerge from the round base of the seed over the next two to four weeks. Plant the seed before the roots get more than ½ of an inch long.
Prepare an 8-inch pot to grow the avocado in. Fill it with lightweight potting soil. Push aside enough soil so that the seed is buried with the top level of the soil.
Set the rooting seed in place gently. Do not break off any roots. Press the soil over the seed. Water it gently until the water runs from the bottom of the pot.
Place the avocado in a warm and sunny place inside or outside when the weather is about 70 to 75 degrees F.