Avocados (Persea Americana) are easy to grow and a project to help kids learn about plant germination. Trees grown from avocado seeds may differ from their “parent” plant because of grafting, but in seven to 15 years, you will have a tree that can start to form fruit. If you would like some homegrown guacamole with your chips for a future Super Bowl, start planting your avocado seeds now.
Retrieve a seed from the inside of a mature avocado and clean it by rinsing with plain water.
Pierce three toothpicks into the seed, equally around its center. Fill a glass with tepid water. Using the toothpicks as supports, suspend the seed inside the glass, immersing 1 inch of its broad end into the water.
Place in a warm spot out of the sun. You will see roots and a stem start to sprout in approximately two to six weeks. Replenish the water as it evaporates.
Trim the stem back to 3 inches with plant clippers when it reaches 6 inches.
Transplant into a 10-inch pot filled with rich potting soil when the roots grow thick and the stem starts sprouting leaves. Leave the top 1 inch of the avocado seed uncovered, above the soil. Move into sunlight -- the more the better. Keep the soil moist, but not saturated.
Trim the stem back to 6 inches, to promote new shoots, when it reaches 1 foot high.
Grow your avocado tree in the pot; pinching out some new leaves to promote bushiness. Keep the soil moist, but not saturated, until its roots completely fill the pot. Then transplant into the largest pot you have room for, filled with rich topsoil. Replenish the top portion of the pot with fresh compost and topsoil each year.
Transplant your avocado tree into your yard if your climate permits. Avocados are native Mexican plants and prefer a semi-humid climate of 60 to 80 degrees F, even the hardiest variety will freeze below 25 degrees F.