You can use any mango from the grocery store, but it's a good idea to make sure you use the seed of one you really like as far as taste or whether it's organic or not, and you can buy organic potting soil to keep it organic.
After you slurp up your fresh juicy mango and are left with the inner seed husk covered in mango hairs, wash it really well under running water and either use your nail or something like a brillo pad to scrape off all the fibers so that you are left with a clean husk.
Set the husk aside on a paper towel for 2-3 days until it is completely dry and begins to crack apart and the seam. Now you can pry it apart with your hands or a butter knife (be careful of the seed inside though!), and you will find a seed that looks like the one above.
Let the seed sit for another night or so to dry out the thin brown outer layer, then peel as much as you can off of the seed. Your seed may already have a little tail sprout at the bottom pointy end... this is great!
Plant the seed into a 6 inch pot pointy side down. The round side (right side in the photo) should just poke out of the dirt. Keep the pot in a warm sunny place that can reach about 80º F. It helps to put a plastic bag on top of the pot or prop some plastic wrap over the top to create a mini greenhouse. I definitely don't have an area that gets 80º every day, so I am using the plastic wrap trick and at night I keep the pot next to the heater so the seed won't go dormant.
Water the seed each day but make sure not to over-water it. The soil should be moist. It will take about a month to sprout on the top end of the seed, and once this happens re-plant the seed in a larger pot to get ready for a mango tree!
*I will post some photos once my seed sprouts, I have had it for about 3 weeks. I thought it might have gone dormant a few days ago so I started digging up the seed only to find a huge root growing at the bottom!
**This plant, once started, is a long term investment. It will take 5-7 years for the tree to fruit, and keep in mind that a full size tree is very large. If you want to plant outside you should live in a very warm southern climate, otherwise keep it as a house plant and continue to re-pot the plant as needed while it grows.
P.S. Keep an eye out for a guest post coming soon!