Why Aren’t my Clones Rooting?

This is a question that many growers tend to ask themselves; why aren’t my clones rooting? There can be many reasons but when it happens and you have no idea why it tends to be down to a small minor mistake that was made when making the cuts or during the rooting process itself.

In this article we’re going to go through a series of mistakes that people tend to make which can then cause the downfall of your clones. We’re going to talk about rooting clones in rockwool, jiffy’s or small flower pots, as all three methods are done in more or less the same way.

Mistakes when taking cuttings:

• You need to take the cutting from the mother plant in a way so that you can then bury one of the nodes in a flowerpot and still have space between the substrate and the first leaves on the clone, so that there’s ventilation and you don’t get any rot. Taking cuttings that are too small will make it harder to spray them properly.
• The rooting medium must be humid, having used water with a pH of 6.0, which will immensely help them to root properly.
• Make sure you don’t wet the medium too much as the trunk might rot and then it won’t root at all.
• Another common mistake that people make is scraping the cutting too much when taking it. Cannabis plants have natural rooting hormones under their second layer of skin – if you peal this skin too much they will never root.
• Cutting at a 45º angle is done so that the stem doesn’t get blocked up, but if you directly submerge the stem into your rooting hormone then it can still get blocked. The trick here is to take a little brush such as an eyebrow shaper or a small, thin paint brush and use that to spread some rooting hormone on the stem.
• Rooting hormones are alive, and sometimes you can ruin them if you contaminate them with something. Every time you take cuttings, pour a little bit of rooting hormone into a shot glass so that you’re not contaminating the contents of the bottle – keep the bottle in the fridge as it will last much longer without going off.
• You need to cut the leaves slightly when you take cuttings but make sure you don’t take too much off – leave around 60% of each leaf on the plant.
• It’s practically impossible to do this without a propagator or small greenhouse, as humidity needs to be at around 90% for them to root. I’ve tried it in all sorts of ways but the best one without a doubt is doing it in a propagator made specifically for rooting cuttings.

Mistakes when maintaining cuttings:

To keep your clones alive while they root you need to follow a series of steps that if not done correctly could cause your clones to die off – if you follow these steps and don’t make any of these mistakes your clones will have a happy, healthy future ahead of them.

• When planting the cuttings, you need to wet your rooting medium such as a jiffy or rockwool – and then you don’t need to water it again until they actually root, around day 10 after taking the cuttings.
• Don’t spray them on the top of the leaves, but rather on the bottom of the leaves – if you spray them when they’re standing upright you’ll wet the substrate and they’ll take much longer to root. You need to remove them from the propagator one by one, spray them outside the propagator and shake the excess drops of water off of them before sticking them back in. If you have them in jiffy trays or rockwool trays you can cut them in groups of 10 (2×5) which you’ll be able to easily remove with one hand, spray upside down and put them back in.
• You need to keep them at around 22º – if they get too cold they won’t root at all, and if it’s too hot the roots will die off instantly.
• You need to open the lid once a day so that they get some new air, as well as drying the drops of condensation on the inside of the propagator. If there’s water on the bottom of the propagator you’ll need to dry that too or the substrate will get too wet.
• You don’t need to water the substrate or use anything in it – once the cutting roots and you can transplant it there will be time for watering and nutrients.
• You need to spray them every second day, opening the lid every day though.
• Don’t let them get too hot – there are heating blankets especially made for them, but electric blankets used around the house can easily kill them off.

Whichever way you decide to do it, you should go check out our article on making cuttings as it has a lot of valuable information on the whole process.

If you have any questions don’t hesitate to leave a comment and our team of experts will get back to you as soon as possible.

Author: Javier Chinesta
Translation: Ciara Murphy