Germinating Green Coffee Beans: Trials 2... 3... more?? | Coffea arabica #2 

Fresh cherries will need to be pulped before planting. I also suggest a thorough washing to remove as much of the cherry and slippery pectin as possible. This stuff is food for microorganisms which will promote infection. When processing a lot of seeds at once, farmers will usually let the seeds ferment for a day or two to help remove the pectin just like in normal coffee processing. You can chose to remove the parchment or not. Leaving the parchment in tact will delay germination by about a month though I think the total germination rate remains roughly the same. Removing the parchment increases the risk of infection slightly. It isn't too difficult to do by hand if you only have a few seeds. You're right: no soaking step is needed. Just plant them about 1 cm deep in well-draining mix and keep moist and warm. Good quality seeds with the parchment removed will germinate in about three weeks.

I have never used ozone, personally, but I don't see any major issues. It's a common disinfectant for municipal water sources. Ozone has about 50% greater oxidation/reduction potential than chlorine. However, ozone has a maximum solubility of ~25mg/L in room temperature tap water. The bleach solution I use has about 20 times that concentration of chlorine. From my preliminary research, it seems that ozone water is relatively safe for seeds and sometimes beneficial. The amount of disinfection will depend on the concentration and exposure time. What sort of ozone generator are you using? Here's a good review: www.tandfonline.com/doi/abs/10.1080/01919512.2019.1673697 Ozone is an interesting disinfectant. I might look into that more for future research. Thanks for the idea! Any organic material will help convert the ozone back to regular oxygen. I would definitely use a carbon-based potting mix like peat or coconut coir. What sort of seed starting mix were you planning on using?

@@electricveg A friend of mine gave me a book called Flood your body with oxygen by Ed McCabe. In that book mentioned using ozone with your plants. I bought a small Ivation-Portable-Ozone-Generator-600mg and i am using rockwool plugs and than hopefully move them to a rockwool cube. I put the rockwool in RO water and ran the ozone through a air stone for 30 minute. Before planting the seeds I did the same but for only for 10 minutes. I plan on growing them the whole way in a hydroponic system. Not sure witch one yet. leaning towards the dutch bucket method.

I just checked and the beans used in trial 3 are all washed. I suspect that the parchment layer protects the coffee beans from the effects of washing. Though maybe the additional washing step reduces contamination by limiting the amount of residual sugars. It's an interesting hypothesis that needs testing.

@@electricveg there are varios forms of processing beans, unwashed (or natural) dries the beans with the fruit still on, the coffee gets more characteristics from the fruit (and also can get some funky fermented flavors)... But it's known that the beans absorbs sugars from the flesh of the cherry... I'm quite sure it would have an impact on the germination! More complicated to test, but maybe something to have on the back of your mind? Another possible factor?

1) I have always done the ethanol wash first. I agree that ethanol would be toxic to the germinated plant. It might be somewhat damaging even before then, but you have to weigh the risks of contamination vs. the risk of seed damage. I wish I could get seeds with their parchment layer intact. That way, the seeds could be sterilized without fear of hurting the cotyledons and embryo inside. If I ever get to the point of selling coffee seeds, that's how I'll do it. 2) Just last week I discovered that the sole survivor from Trial 1 had lost its root. Both of your explanations seem plausible. I have read some mention of aborted root growth in the literature, but they didn't provide a specific cause or solution. I'll have to do more research. 3) If you presoak your seeds, coarse vermiculite is actually better. Fine germination media is good for hydration because of the increased contact between the wet media and dry seed. If your seeds are already well hydrated, they will probably benefit more from the increased aeration of coarse media. When it comes to the germination of commodity green coffee, I think filter paper on Petri dishes are the absolute best option. In my experience so far, you end up tossing 90+% of the seeds. It makes things so much easier to visually inspect each seed for contamination, exudate, and growth. My next coffee video will be about this method in more detail. In the meantime, the wet paper towel in a baggie method is a good low-cost alternative. Coffee filters in small plastic containers work too. If you have any more insights, please don't hesitate to leave a comment. Trial 3 has only 5 germinations out of 72 seeds, so there is still a lot of work to be done.

@@electricveg Thank you for the quick response, and sorry to hear about your seedling 😢 I'm getting 50 seeds from Hawaii next week, so I hope they will fare better than the commodity green coffee from my last attempt! Another question, which also happens to tie into a theory for the roots falling off: how often do you think vermiculite be watered? Should it be more by observation of dry soil, or be strictly periodic? I suppose that I may somewhat be underestimating the water retention that comes out of prolonged soaking. I noticed that one of the roots fell off while soaking, it also happened to be the first one that sprouted in that batch. I'm wondering whether overhydration may be a potential culprit for this issue

@@Remy0313 Vermiculite doesn't really change color when wet, so it might be difficult to judge when to water by appearance. Verm has a good water:air ratio, so you can place it directly into a small pool of water. I'm having my doubts about one of my statements from the first video about initial root formation. The more that I think about it, the green protrusions seen in the first few days of soaking can't be roots. They must be some form of leftover stem that engorges with water.

All excellent ideas. You hit all of the talking points for my next update! I think exudate color monitoring is a good option for distinguishing nonviable seeds and removing them early. I've been using the technique in trial 3. doi.org/10.1590/S0101-31222012000200004 Trial 3 used only 24 seeds per group and they were leached in 1 liter of water, exchanged twice. Microbial degradation of caffeine is one of the protecting factors in the traditional soil cultivation of coffee. It's the storage and transport of commodity green coffee beans that infect them so heavily with pathogenic species. I think one of Pseudomonas spp. could be used as you suggest. They are included in a couple of commercial beneficial microorganism inoculants. There's more current info on my progress at www.electricveg.com/rubiaceae/coffea-arabica.html#work-log

I should have included this note on my coffee growing journey (so far): Before I even saw this video I ordered unroasted gesha coffee from several suppliers to start my own gesha seedlings. They will arrive within the week and I need to work out a methodology to tackle it. Last week I received 5 green geisha beans that I decided to rehydrate in dilute Worm Gold worm casting tea. I planted each in a 50/50 mix of coco coir/coarse sand in 1 gal pots and stored them in a protected location outdoors (San Diego, its 40s at night 70s in the day right now). My other coffee plants are doing fine outdoors (all seedlings from 4in pots at Home Depot) so while I don't expect quick germination it is a fun 5 bean experiment.

@@electricveg Hey, So today I started soaking a cup of green gesha beans (washed process) at around 1pm, changing the water every hour or so. Its 9:30pm now. Unbelievably, I found 12 beans that already threw out root shoots so I potted them up and added mycorrhizae fungi to the soil mix. No dried roots were visible prior to rehydration but it is possible these could have been remnants from an aborted germination. I am gonna see if they grow and try soaking another cup of beans tomorrow :) 1/31/22 11:54AM I am doing a wash followed by a drained technique on the remaining beans. They sit in the sealed drained container for a couple of hours then I do a wash again. I found 4 more sprouted beans that I removed for germination. I don't know whether this batch of coffee beans was particularly viable or if this technique is worthwhile. Here is the link to the beans that I bought for this. www.etsy.com/listing/1109005489/organic-green-geisha-unroasted-colombian?ref=yr_purchases 2/1/22 For several of the beans that have shot out radicules I am keeping them in a small plastic container, washing twice a day, followed by draining, replacement of the lid and germination in a dark space. The radicules seem to be growing very slowly and no signs of mold so far.

This batch, as well as a batch with a 30min Hydrogen Peroxide wash got infected with blue-green mold. I don't know if it is something in my tap water. I need to boil the tap water or use distilled next time. My next batch will use oven-baked sand, 30min Hydrogen Peroxide soak and boiled, cooled water for hydrating.

@@jameslively4487 I have never tried peroxide disinfection. For some reason it isn't well represented in the literature, but I don't know why. It might be worth testing further washes with disinfectant after mold is detected. Though the seeds might already be dead by the time the mold is visible. Keep up the good work!

Any updates?

@@Anw120 nothing. They all died, apparently. It seems they need to be from the berries (fresh).