Pineapples (Ananas comosus) are native to South America, probably the region where Argentina, Paraguay and Brazil meet. By the time Columbus visited America, pineapples were already being grown throughout South and Central America. This tropical plant grows in U.S. Department of Agriculture plant hardiness zones 10 through 12, and doesn't do well if temperatures drop below 60 degrees Fahrenheit. Pineapple is a bromeliad, and needs full sun to form fruit. It now grows in tropical areas worldwide.
Commercial varieties of pineapple don't produce seeds and must be propagated from suckers or stem cuttings of the mother plants or from the crown of a pineapple fruit. Once rooted and planted, suckers will flower and produce fruit in 12 months. Rooted crowns will take 18 months to form fruit. For Hawaiian pineapples, the main fruiting season is from April to May. Pineapples grown in the Caribbean have two fruiting seasons, December through February and August through September.
A pineapple fruit is a composite structure made up of many fruits all fused together. A reddish-colored flower stalk emerges on mature plants and blooms for about two weeks, pushing bluish-lavender flowers out between the bracts. Each flower produces one of the diamond-shaped fruits that form the body of the pineapple. Flowers don't need to be pollinated. Fruits are most delicious if allowed to ripen on the plant, but they don't ship well when ripe. Pineapples didn't become a commercial crop until refrigerated ships and air transport could get them to market quickly. Pineapples don't continue ripening once they're cut off the mother plant, so they are picked before full ripeness. Hawaiian pineapples take two to four days for air transport to markets. Central American and Caribbean fruits take four days to two weeks to arrive by boat and truck.
A smaller crop of off-season or second-season fruits can occur six months after the main fruiting time. Growers can produce fruits off-season by using substances that mimic the natural plant hormones that stimulate fruiting, such as acetylene, ethylene, calcium carbide, smoke, and napthaleneacetic acid. In Costa Rica, pineapples are picked green and ripeness is controlled during shipping by controlling the temperature and introducing plant hormones that produce ripening.
Fruiting in Houseplant Pineapples
Pineapples are suitable as houseplants anywhere if you can give them sunlight and warm temperatures year-round. Cut off the crown of leaves from a pineapple, trim away the fruit and root the crown in a 6-inch nursery container filled with half sand and half peat. Transfer the plant to larger pot sizes as it roots and grows. For full-sized pineapple fruits, the plants need to be about 6 feet tall and as wide, but you can force the pineapple to bloom and fruit in smaller plants regardless of what season it is. The fruit will be small. Place the plant in a bag with a ripening apple, which produces ethylene gas. This induces the pineapple to flower and then to fruit. You may need to treat the plant over a month or two and replace the apple several times.
- Smithsonian.com: Food & Think: It's Pineapple Season, But Does Your Fruit Come From Hawaii?
- Produce Pete: Pineapple
- Floridata: Ananas Comosus
- United Nations Food and Agriculture Organization Corporate Document Repository: Leaflet No. 10 - 1986 - Pineapple
- Texas A&M University Aggie Horticulture: Texas Citrus and SubtropicalFruits: Home Fruit Production-Pineapple
- Marietta College Biology and Environmental Science Department Field Trips: Costa Rica 2005/2007: Pineapples Costa Rica
- The New York Times: A Guide to Choosing a Ripe Pineapple
- New Mexico State University College of Agricultural, Consumer and Environmental Sciences: Extension/Outreach: Growing a Pineapple Houseplant
- Comstock/Comstock/Getty Images