These are easy to grow. Every time you buy a commercially grown pineapple simply remove the top, let it dry a few days, and then plant it. If you are braver, you can cut the crown in half and let them dry a bit, and plant each half. You will then get two nice plants in short order. They do not take long to root.
You can cut the crown into quarters, or even more divisions, and still get viable plants. I’m doing that now with a crown that had rotted in the center, figuring there was nothing to lose by trying. So far, the divisions seem to be hanging on after being planted two weeks ago. I do not know what the limit is, but it would be fun to find out how many plants you can really get from one pineapple top.
My limiting factor is dirt. Florida dirt is awful poor stuff. But with composting you can make more, if you are patient. We can plant pineapples directly in the ground, but as they are a pain to weed around, so I usually stick with large pots, and with a mix of topsoil and composted cow manure.
They don’t bear fruit right away; usually they take three years before a crown-derived plant produces a flower and fruit. Sometimes a plant will develop one or more pups or shoots on the fruiting stem below the fruit; I have been told that these pups will produce fruit in just two years.