Monday, April 15, 2013

Random plant event: Coffea arabica

It's been a couple weeks now since the first Coffea seedlings emerged from the vermiculite, which may be a good time to report on what's happened since then.

The news I find most interesting is that, of the two groups of seedlings (those dried for eight weeks prior to sowing, and those dried for only four or five days prior to sowing), the eight-week group is clearly and obviously doing much better than the five-day group. By this point in the process, I've gotten 100% germination (18/18) from the eight-week group --

-- and only 11% (1/9) from the five-day group:

Obviously there's still time for the remaining eight seeds to sprout, but they only have a month left, and I'm not optimistic about them. So we've learned something. If you're going to sprout Coffea seeds from berries, here's a procedure that works:

1) Remove the seeds from ripe berries.
2) Soak the seeds in water for 24 hours.
3) Remove the seeds from water and let dry for eight weeks in a warm, dry spot with good air circulation and no sun.
4) At the end of the eight weeks, soak the seeds in water again for 24 hours.
5) Plant the seeds 1 1/2 inches (~4 cm) deep in damp but not sodden vermiculite, ideally in a pot that's taller than it is wide, and cover the pot to keep in moisture.1 Place under a light source, in a warm location,2 and wait; you should see the first sprouts in about a month.

But the specific occasion for the post is that there are now cotyledons3 visible:

Which is exciting.

Also noteworthy: a lot of the seeds had some gray fuzzy fungus on them once they emerged from the vermiculite. This doesn't appear to have affected the seedlings or their germination any, however worried I was to see it initially.

It's possible that the black stuff on the seed coat, two pictures up, is another fungus, or is related somehow to the first fungus. All I can tell you at this point is that it's surprisingly fine and sooty.

The next Coffea update will probably be when they all get transplanted to soil; I have no idea when that will be, though. I'm not sure how long they can (or should) continue to grow in the vermiculite, and I don't want to try to transplant until I'm fairly sure they have root systems that can handle the shock. So we'll have to see how it goes, I guess.


1 Because I didn't want to have to worry about watering them, mine were actually completely enclosed: the black tray they're in has no holes in the bottom, and then they were covered with a tight-fitting clear plastic top. I'm not sure if this particular detail of my process should necessarily be imitated by others.
2 The basement's not really all that warm. Maybe 72-76F / 22-24C.
3 ("Seed leaves")


Ginny Burton said...

Those are impressively sturdy stems -- congrats!

Ali said...

I just checked my coffee arabica at work and saw that it had a single flower, how funny that you should also have a coffee event today!

Anonymous said...

Just a heads-up, when I germinated coffee seeds a few of them got "stuck" in their seed coat for a few weeks until I eventually gave in to the risk of cotyledon damage and helped free them.

Cassidy said...

The tidbit about the drying time if the seeds is really interesting. Thanks for the update!

mr_subjunctive said...


I appreciate the tip. (Just went down and checked. Everybody was fine so far, but I went ahead and pulled the seed coats off of a few of them anyway.)


I've been really surprised at just how many kinds of seeds do better after they've dried out a little, instead of being planted directly. (e.g. Schlumbergera)

Paul said...

I do realize this is just symptomatic of an overactive imagination, but that first photo? What it reminded me of was one of those pictures of palm trees in California or Florida when taken from a long distance away ... the long bare trunks topped with a tuft of leaves. heh

mr_subjunctive said...


I actually had the same thought. Apparently there's something about the propoprtions.

Kapt'n Splash said...

Just my slightly random experience with growing coffea:
I was able to get three little seeds to plant a wile ago(mid February). I dried them for only about 4 weeks, and then wrapped them in wet paper towel in a zip-lock baggie (like growing bean seeds in elementary school). one I could see a root start to form and the others I saw nothing. I planted all of them anyway and the one started coming up fine, while the others appeared to do nothing, but I kept them for a few weeks anyway. now, almost 2 months after planting, the original sprout has had an accident and got its stem snapped, but last night I saw one of the others has sprouted, but with no signs of the cotyledon leaves coming free of the seed coat at all.
My only question is do you think its too soon to risk freeing the leaves?

mr_subjunctive said...

Kapt'n Splash:

Yes. I mean, I don't have any particular expertise on the problem, bear in mind, but if it's only just sprouted, I wouldn't expect any cotyledons to show immediately. I'd give it a couple weeks at least. None of mine have shown any tendency to get stuck -- when I've pulled seed coats off, it was mostly because I didn't want the seed coat to fall into the vermiculite and rot there, not because I thought the plants weren't going to be able to push them off on their own. Don't rush it.