Pineapple is probably the optimal exotic fruit anyone can grow indoors anywhere. Easy to plant, easy to grow and will produce a juicy, sweet pineapple within about 3 years. Unlike all avocado seeds, which get crucified over a glass of water (at least it’s popular to do so here in Sweden) and which will never get into anything more than scrawny little tree. Pineapple can be a fun home project to do with the kids or on your own.
There are hundreds of YouTube clips out there showing how to grow pineapples. Yet, I decided to do another one. The reason is in widely spread misconception that you suppose to grow first in water to get the roots and also most of them won’t tell you how to made the pineapple flower and bear fruit the sure way. I do it in my video showing my own home grown pineapple and the whole easy procedure. Those who prefer reading can do it below the video.
Buy a pineapple with healthy inside part of the top
If you are not already growing your own pineapples, you can just get one in any fruit counter. What you should look for is the one with the top which has healthy centre or the rosette. It’s where the new growth comes from and where eventually the flower will emerge.
The maturity of the fruit you buy doesn’t matter.
Twist and tear it off, don’t cut off
You separate the top from the fruit by simply turning it and pulling off. This way you get a much smaller area for the bacteria in soil to attack your newly planted pineapple. This is compared to cutting with a bit of the fruit left attached to the top as some would recommend. People argument that it suppose to give the new plant some initial resources before it grows the roots and start eating self. However, that’s not how it works. So just tear it off.
Pick off the outer layers of small leaves
Tear off the outer layers of the leaves until you get about an inch (2-3cm) of bold stalk. On mature pineapples you can often see small roots already developing there between outer leaves. Put your top aside for at least a couple of hours before planting so it get a protective dry scar surface.
Plant directly in soil
Do not put it in water first, as many would suggest. The roots developed in water are adapted to grow just in water. They are useless when transferred later into soil and the young plant will have to grow another set of roots and that is energy consuming.
Take a small pot about the same diameter as the pineapple top itself. Prepare a well drained soil mix by adding about 1/3 part of the volume of perlite to the regular potting soil. Don’t forget to add a drainage layer of leca in the bottom of the pot. The pot must have drainage holes. Complete with a tray to put it on for the excess of water to come out into.
Plant it with the peeled stalk covered by the soil and put it in a place with at least room temperature. Don’t put it in a bright location yet. It will get roots within a week or two and then you can transfer it into the sun.
Keep it warm and sunny
As the tropical plant it is, pineapple should be kept warm, at least room temperature all year round. Try to place it into your sunniest spot. If you don’t have a south facing window you should consider giving it an artificial light.
Keep the water standing in the rosette
Being a member of the bromeliads family, pineapple, like most other bromeliads are designed to accumulate water in their rosette, the centre part of the leaves. A newly planted top has probably not so dense rosette to hold the water, though in the beginning water it into the soil. When it start growing bigger and tighter you should switch to watering into the rosette instead. Try to keep some water standing there all the time and water the soil only when it gets dry.
Fertilise your pineapple
Like all plants, pineapples need some food as well as water. You can use your regular house plants liquid fertiliser about once a month. If it’s organic fertiliser, it’s better to use it in soil. Otherwise you can water it into rosette as well.
Replant into bigger pot
When your plant get about double the original size, it’s time to upgrade it into a bigger pot. Take about 6-8l (1 1/2 – 2 gal) pot and prepare the same well drained soil mix as above, drainage layer and a tray. Pull you plant out of its old pot and without loosing up the roots just transfer it into the new pot and fill in the empty space with new soil.
Give it a haircut
Pineapple leaves can grow about 1m (over 3′) long with sharp tips and some thorns on the edges here and there. If you have problems with this appearance, you can cut the leaves keeping the plant diameter of about 60cm (2′). Such haircuts don’t seam affect the plant negatively.
Make it flower
Pineapples are unreliable bloomers. Mature plants can take different time to start flowering and the difference can be years. Fortunately there is an easy trick to lure them into bloom. That is how they are doing in commercial plantations to make sure they can harvest a pineapple field at the same time.
Ripening fruits produce acetylene gas, which cause a hormonal reaction in pineapple plant making it to set a flower. One of the methods circulating on the net is to put a ripe apple in the pineapple pot and encapsulate it in a bag. The problems I see here are in relatively small amount of acetylene produced by an apple and in putting a large sticky plant in a bag.
Instead I’m using a small bit of calcium carbide (just about 1/5 of a thumbnail), which I put in the water filled rosette. The instant reaction of calcium carbide with water produces a lot of acetylene gas. Such a quick and easy treatment practically guarantee that in about a month later you will see a flower coming up in the middle of the rosette (see the photo gallery below).
Do it in the end of winter on a mature plant so that the fruit will ripen during the summer time.
You shouldn’t buy large amounts of calcium carbide as its storage require some special safety precautions. Acetylene gas produced in calcium carbide and water reaction is highly flammable.
Let it ripen
It will take 4-5 months from you see the first sign of a flower to a mature fruit. It will get a golden yellow color and the stalk where the fruit is attached will droop. Then it’s harvest time!
You fruit won’t be as large as those in supermarkets. That’s because those commercially produced pineapples are treated with growth hormones. So even if your top is coming from supermarket fruit, your home grown plant will reverse to its true nature. It will be smaller, but also so much sweeter!
Start it over
When your pineapple plant has rewarded you with your own, home grown pineapple, it will slowly die. Most probably it will produce one-two root shoots of new plants. You should wait them grow a bit bigger before separating them from the dying mother. Also you can just start it all over by planting the top of your fruit.
Here you can see a pineapple from starting at the middle of rosette to flowering and ripening: