This ended up way longer than I intended so I apologize. But cloning used to be my weakest area and I absolutely despised the process. Turns out that its way simpler than I thought, and internet information was just overcomplicated and un-necessary.
Just keep popping seeds at all times! Most plants from pops truly are not worth cloning, and can often be found again in repeat seed pops. But every now and then you will get a plant that makes you go “holy shit”. For situations like this, it is great to have cloning protocols down reasonably well. And it definitely helps to grow the plants in a way that allows for easy re veg, just in case you find a real unicorn. Passing that cut back to a breeder could really help expand the gene pool in a positive way!
Cloning is really really easy, but is made complicated by people trying to take your money. After going through all sorts of advanced protocols and stupid bullshit I read on the internet, I threw all of my methods away and went back to trays and domes. Its just stupid simple now.
There are a few things to consider when cloning. Understanding all of these variables basically guarantees success, as you will be able to make decisions based on your understanding of the cloning process. Rather than following arbitrary steps and bad practices posted on forums.
Mold is the main enemy when cloning with domes, but is easily taken care of with clean practices. Clean equipment and periodically exchanging air is all you need need to do for this to work! If there are no mold spores, its more of a “when” rather than “if” the cuttings will root.
Now we have to determine what is actually happening during the cloning process? Why are we doing what we are doing… Basically… Plants cannot regulate their rate of transpiration. So in a “normal” growing environment they are allowed to transpire at a very high rate, but do not have a root mass that can keep up. We, as growers, can regulate this rate of transpiration via vapor pressure deficit. The higher VPD is, the faster plants transpire. The lower the VPD, the slower they transpire. So we use domes on fresh cuttings to dramatically reduce VPD via increasing humidity. This reduces transpiration and allows cuttings to maintain their turgor pressure. This gives cuttings time to develop new roots. BUT it is also the perfect environment for mold growth. This period is where most people fail, because mold infections out pace root development. This is basically day 1-7 or so.
After time, the plants will go through what is called direct organogenesis, pushing new root cells out of the stem of the cutting. Once this immature root structure is formed, the cuttings are now full fledged plants and only need to go through the hardening process. At this point, you are good to go as long as you didn’t see any stem rot. You just have to remove the dome for a progressively longer duration of time over the course of 3 or so days. Once the dome is off, risk of mold almost entirely disappears. New roots typically appear on day 7-8. Those roots can be allowed to mature in the dome through day 10-12. Then we can harden the plants off at our own pace.
- Get a tray, humidity dome, and tray insert if applicable.
- Spray/wash down the dome and tray with 4 tbsp bleach per gallon. Assemble tray and dome and close vents while it is still wet. This allows more dwell time. Let it sit for an hour.
- Open it up and either wipe down with paper towels, or let it air dry. After this close the dome again.
You can do these steps weeks in advance as long as you store the trays with domes on top, vents closed.
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Prepare a full tray of root plugs. Soak them in full strength veg nutrients for like 5 mins. Drain water from bucket, do not squeeze out plugs. Rapid rooters are great. I use iHort 40/40 plugs.
Rockwool is garbage by modern standards, dont use.
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Wash cuttings off in room temp water just to remove any possible spores. I use an oxidizer but you dont need to.
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Dip ends of cuttings in rooting gel (I like IBA based rooting gels, roottech is what I use, but aloe works well too). Then put them in the plugs. Keep all other empty plugs in the tray and moist!! These help maintain the humidity in the dome, allowing for low VPD. If you load up 4-8 cuttings in a dome, it is likely that your plugs will dry out before root formation. I dont like standing water in the domes.
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Put under a 1/3 strength veg light and… Wait until you see roots haha. Avoid poking and prodding as that just introduces contaminates and can lead to failure. Ask me how I know!
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After you see roots, start the hardening process. Remove dome for an hour day 1, then 3 hours day 2, then 6 day 3, then you are done. Plant them.
It sounds a bit more complicated than it really is in practice. Wash trays, wash domes, rinse cuts, dip cuts, set cuts, forget about them for 5-7 days. If they have to be watered, water. Day 12 or so remove the dome, and increase time without dome each day until they no longer droop without the dome. At this point the plugs will dry out quickly so misting the plugs every day with full strength nutrients is best.
