After enjoying the sweet fruit, save your pineapple top and grow your own tropical houseplant. Pineapples easily root from their leafy tops if they are planted and grown correctly. Pineapples are especially suitable as houseplants, because they thrive in indoor temperatures. A pineapple houseplant that is properly cared for will eventually flower and produce small, edible pineapple fruits.
Cut the top off the pineapple with a sharp knife. Trim away the fruit attached to the lower part of the stem, leaving about ½ inch of stem protruding from the leaves. Trim off two or three sets of the lower leaves if necessary to reveal the stem.
Set the pineapple top on top of a paper towel in a well-ventilated area. Leave it to dry for one or two days, as this discourages rot during the rooting process.
Fill a 6-inch diameter pot with vermiculite. Water the vermiculite in the pot until it is evenly moist throughout.
Push the stem of the pineapple top into the vermiculite just deep enough to hold the leaves upright. Set the pot in an area that receives bright, indirect light, and water as necessary to keep the vermiculite moist but not soggy.
Tug gently on the pineapple top after six weeks to check for rooting. If there is resistance, the top is rooted. If the top is not rooted, continue to grow it in the vermiculite, checking it once every two weeks until it is rooted.
Transplant the rooted pineapple to a 10-inch pot filled with a moist, quality potting soil. Plant the top at the same depth it was at in the vermiculite-filled pot. Place it back in bright, indirect sunlight and water often enough to keep the soil moist but not soggy.
Move the plant into a bright, sunny window after it has been growing in potting soil for three weeks. Continue to water it as needed and begin fertilising it with houseplant fertiliser at the rate recommended on the package once a month. Fertilise the plant throughout the growing season, which ranges from spring to fall.
Place potted pineapple plants outdoors during the summer, but bring them back inside before the first fall frost. When the plant is three years old, place it in a plastic bag with a ripening apple for three to four days. This encourages the plant to bloom and set fruit.
Do not overwater the pineapple. Soggy soil causes the plant to rot.