So how to propogate a pineapple plant? Go to the grocery store and buy a pineapple with healthy green leaves. Make sure that the leaves look strong and healthy. If the leaves are brown or orange, do not use it.
Grab the leaves and pull it out of the pineapple. Remove any additional flesh that comes out.
Strip off some of the lower leaves. You do not want anything coming into contact with the soil. Let the crown dry out for a couple of days. (If you grow potatoes then you know why this is necessary.) It will prevent rot.
Place the crown in a clear glass jar. Fill the jar with water. Now we are going to root the plant. (I already tried this process with my basil) In three to four weeks you should see healthy whitish leaves protruding from the bottom of the pineapple base. Remember to change the water in this process. Rooting takes awhile and you do not want diseased water.
Next, pot the plant in some Cactus potting soil. This is available at Home Depot or Lowes.
Keep the soil moist, but never WET. I made this mistake with my potatoes. They will rot.Some of the leaves will begin to turn brown and die. Do not worry. That happens. Do not throw the plant away. Remove the leaves as they die, water just a little only ONCE a week.
After one year of growth, re-pot the plant. It is best to keep this as an indoor plant. But some people have success bringing them outdoors mid spring and summer.