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I found a coffee tree which blossoms and produces coffee "cherries" each year. Last year I harvested a few dozen cherries.

After reading all kinds of "how to grow coffee from cherries" articles which all seemed to give different instructions, I did the following:

  • Separated the beans from the fruit, soaked overnight and cleaned them off.
  • Planted half in soil about 2 cm down right away.
  • The other half I let air-dry for a few weeks and then soaked overnight and planted.

The pots sat right in front of a south-facing window.

I had zero yield. Possibly it was too late in the year and wasn't warm enough inside (no central heat here in Taiwan) and possibly in my enthusiasm, I over-watered.

This year I would like to try again. The tree is currently blossoming and so I expect many cherries later this summer.

Question: What really is the right procedure for growing coffee indoors from cherries? Should they be allowed to dry out before planting? If so, why?


A few of the coffee beans from last year, still in the process of being separated from the fruit:

A few of the coffee beans from last year, still in the process of being separated from the fruit

3 Answers 3

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I think you mostly did things correctly, except in a few points:

  • A couple of sources I saw said you were supposed to ferment the pulp from the seed, while others didn't care how you removed the pulp. I think the fermentation is supposed to aid in removing the seed coat.
  • You need to soak the seeds for 24 hours, not just overnight, to ensure removal or "cracking" of the seed coat.
  • If you do air-dry the seeds, do so only for a few days, not weeks.
  • Don't over-water - the seeds apparently like to be moist, but not wet. This will be the trickiest part of germination, in my opinion, because:
  • It can take 10 weeks or so for a fresh seed to germinate; up to six months for a dried seed.

You're right in that sources are contradictory about whether you should dry the seeds or not after soaking them. It all has to do with the seed coat, so if you notice that the coat has cracked after soaking you can skip the drying part.

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  • OK I will pay attention to these, thank you very much! When extracted from the fruit, the seeds are still wet, soft to the touch and slippery. It's hard to imagine how making them wetter will make something crack. Perhaps it's the drying that helps the coat become a distinct layer that can separate or crack. This year I'll be more careful to keep the soil in the "moist but not wet" regime dutifully for a few months. I'll also start earlier so that they have more time to germinate before it gets cold.
    – uhoh
    Apr 14 at 15:10
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    One source talked about germinating the beans between two layers of the bag the green coffee beans came in. In your case, that would be thick burlap, since you're getting them right of the tree. Keeping burlap moist might be easier than using a soilless mix.
    – Jurp
    Apr 14 at 18:27
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    So, you may have a very long wait for your next cup of joe...
    – nuggethead
    Apr 14 at 20:27
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Assuming that at one point you want to be able to enjoy a cup of your own coffee, let's begin with the growing. Coffee roughly is divided into four species namely Arabica, Robusta, Excelsa and Liberica all originating on the African continent. From the image of the fruit I would guess that what you're growing is Arabica.

People in higher latitudes > 35 deg (up/down) are used to plants and trees which after a more or less pronounced cold period (autumn, winter) life is returning back, plants sprouting, blooming, being fertilized and then growing seeds (aka fruit).

People in lower latitudes < 30 deg (around the equator) are used to pronounced wet/dry periods with temperatures staying well above freezing and plants often having not one, but two fruiting periods. Blooming is triggered by a strong wet period after a pronounced dry period.

To make your coffee bloom, with coffee being a tropical to subtropical plant, use spring and the emerging longer days by taking your plants off the watering schedule for ten to fourteen days. Watch the foliage as your leaves should no go for longer time periods while drooping. After the dry period restart watering with a good soaking, also spray foliage with water to simulate rainfall. Then return to your customary watering scheme the next day.

The trees will bloom and the only thing you have to make sure is that the blossoms get fertilized by exposing the trees to insects (about 40% of the fertilization is done by bees) or using a very fine painters brush you can hand fertilize the blossoms by taking over the work from the insects. Blooming period is short (one to two days) be alert and swift with fertilizing, best done by bringing the pots outside or opening the winter garden.

Now to coffee processing which was the other part of your question. I assume you are interested in so called washed coffee. After harvesting the pulpa (the flesh around the beans) needs to be separated from the beans, which for smaller amounts can be easily hand in the kitchen on a board and using your hands. For slightly bigger amounts one can always use a manual cherry stoner.

If you want to make another product with the pulp then use it for cooking (make a reduction) as a sauce or sweeten it and use it as preserves.

You know from hand processing that the beans are covered in a sticky and slimy material called the mucilage. The mucilage is a coating which contains a lot of sugar (taste it). As you might know sugary things left in the open start to ferment fast due to microbial live (bacteria/fungi), therefore drop all your beans as soon as they are pulped into water and soak them for a few hours. With this you'll get a light fermentation going which dissolves the mucilage.

Fermentation of coffee finds it analog in wine production where the taste of the end product varies with the fermentation process.

After fermentation rinse the beans by rubbing them together in your hands until the beans feel and sound like pebbles, then put them on some drying grid spread out such that they are shedding the water fast, best done by exposing them to the sun. Use a thermal fruit dryer alternatively. Sun drying takes about two weeks for the beans to reach a residual moisture content of about 10-12%.

The coffee beans are now much lighter and have the feel and sound like stiff paper. It is not for nothing that the skin covering the beans is called the parchment skin. This skin needs to be removed to reach the last stage before roasting, namely green coffee beans. This can again be done manually or by spreading the parchment out on a hard surface covering it with chicken wire and walking on it with soft rubber soles (aka Flip Flops).

Phew, now we hand crafted green beans which are ready for roasting. Roasting is again a very involved process which can easily destroy all the hard work so far. I assume as being interested in coffee you might have access to some small scale roasting equipment.

One little tidbit before I conclude, always make sure that you have straight tap roots (never J-roots) by planting coffee into long (2' or 60cm) slim pots

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  • I hadn't thought this far ahead, but this is very useful information. Thanks!
    – uhoh
    Apr 14 at 22:24
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This is a supplementary answer to my own question. It helps to emphasize

  1. what @Jurp's answer points out - it can take 10 weeks to see sprouts
  2. the importance of not overwatering while one is trying to be patient
  3. there is indeed a hard coat on the seed, and I can see why it might be beneficial to help it "crack"

After waiting some period probably less than 10 weeks (and a reminder that it had gotten cold by then, despite the sunshine during the day) and with me possibly overwatering the whole time, nothing happened. So I recycled the soil and used it to plant some roselle seeds. I this spring I discovered several sprouts that failed - it looks like they could not break out from there somewhat rotten-looking shells, and one sprout with green shiny leaves that looks quite a lot like a coffee sprout and can't imagine what else it is.

So by accident, I have one sprout from the old batch, and looking forward to trying again this year!

Also, here's an old seed that had originally floated when soaking so was discarded, but I found it again. When really dry, there is indeed a very hard shell. I needed to use scissors to cut around the edge of the seed before I could open it up.

It had the consistency of the shell on un-popped kernels of popcorn at the bottom of the box in a movie theatre (remember those?)

It makes me wonder if I should be nicking the seeds before planting them to help this along.

yay! one coffee sprout amongst the roselle

uhoh! three failed coffee sprouts amongst the roselle

an old, dry (and rotten) coffee bean and its very hard shell

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