From: pharvey@quack.sac.ca.us (Paul Harvey)
Subject: more info on forcing pineapple/bromeliads to flower and fruit
Organization: The Duck Pond public unix: +1 408 249 9630, log in as 'guest'.
Date: 13 Dec 1992 10:27:12 UTC

Ref: CRFG Fruit Grower, Dec92, V24#6, Fullerton, CA, ISSN 1049-4545,
"Sapotes and Other Subtropicals in the Low Elevation Desert of Arizona",
Alois Falkenstein, pg 6:

The pineapple is one of my favorites. The plant is ornamental and a
properly ripened pineapple is one of our world's finest fruits. One of
the problems with the pineapple is that it flowers erratically, and it
is customary to force mature plants into producing fruits by the
application of various agents. The home gardener with a few plants or
the small farmer in tropical areas frequently uses calcium carbide.
Approximately 10-12 grains are applied to the terminal bud at night.
Considerable heat is produced when it reacts with water to release
acetylene gas.

The first pineapple I tried this on was burned. My next pineapple was
treated with a calcium carbide solution (30 grams in 1 gallon of water).
This achieved better results. I did not like working with the calcium
carbide and reviewed the literature for other methods of floral
induction. A newer method is ethylene forming hormones.
A-naphthaleneacetic acid or B-naphylactic acid (1 gram in 10 gallons of
water) is applied as a foliar spray (this is approximately 0.003%
solution). I found that Tomato Blossom Set Spray carried at the local
nursery is B-naphylacetic acid and is present as a 0.003% solution. I
apply the Tomato Blossom Set as a foliar spray and place a small amount
in the central rosette and within a month, I have a blomming pineapple.

I have also used ethepon to induce fruiting. Ethepon is one of the
preferred methods in commercial use for induction of fruiting in
pineapples. When it is applied, it breaks down into phosphoric acid and
ethylene gas. Ethepon is considered one of the most reliable methods to
induce fruiting. Ethepon is also used to *prevent* various trees from
setting fruit, especially olives. The brand of olive-stop I use is
distributed by a Fresno, CA firm. Its package insert also has
instructions on how to use this agent to increase fruit set in tomatoes
and how to induce flower production in bromeliads. [Pineapple is a
bromeliad.]

I have found that with any of these methods, floral induction works
better if one doesn't fertilize the plants two weeks before or after
treatment. Although the ethepon produced the most reliable results, I
found that B-naphylacetic acid purchased as a Tomato Blossom Set is the
simplest to use for someone with only a few plants. If you are going to
purchase an agent for floral induction of pineapples, be certain that
the agent is approved for such use or obtain advice from you local
department of agriculture.

Ref:
Morton, Julia, F. (1987) Fruits of Warm Climates, Media Incorporated,
Greensboro, NC
Samson, J.A., (1986) Tropical Fruits 2nd Edition, Longman Inc, NY
Malo, S.E. and Campbell, C.W., Fruits Crops Fact Sheet, The Pineapple
FC-7, Florida Cooperative Extension Service, UofF, Gainesville.

BTW: If you want to grow your own pineapple, (they make great container
plants), just twist the top off a fresh fruit and peel the lower leaves
so that you expose about a one inch stub. Let the plant air dry for
about a week, upside down, in a shaded ~70oF location. Then plant into
sterile potting mix and slowly introduce to brighter light and finally
full sun when fresh growth is observed. Be careful you don't overwater,
these plants are drought tolerant and are easier to rot then to
underwater. Keep soil and water out of the center until the plant is
growing then water and soluable fertilizer can be applied to the center
and leaves (foliar). Expose to as much sun and heat as possible and
protect from freezing. After about 18 months, if it hasn't flowered, try
the Tomato Set as above. The original plant will die after fruiting and
should be removed and one of the new plants, slips, that form around the
sides should be selected as the next plant. All other slips should be
removed to other pots. Now you're in the pineapple business. Enjoy!