You’re reading this article and, maybe, this is the first time you’re rooting hoya cuttings.
I remember rooting my first hoya very clearly back in 2016. You can read about that experience in detail here
Some hoyas will strike roots faster or better depending on the media used. Over the years I’ve used water, then soil, then soil with sand or perlite and then, now, just perlite. This article is about using perlite .
Look at the picture of two Hoya Vitelinoides cuttings (picture taken in July 2019)
You can see how the cutting on the right, rooted in pure perlite, has a greater root mass than the one on the left, which rooted in a mix of 50/50 perlite and compost. So, I’ve found that perlite is the best medium for rooting cuttings; It will give your plants the best chance at forming a strong root system early in life before being moved to a different mix for growing.
In this method i used two strawberry containers of the same size. One holds the perlite,the other creates a mini greenhouse. The two halves can be held together with selo tape and then be placed in a saucer by a window. This method will work during the growing season, but it’s not recommended during the winter as more light and warmth is required for rooting.
Note: for quite little, a small heat mat and LED light could be used to boost rooting in the summer AND make it work in the winter.
What follows here is my method of rooting Hoya cuttings in bulk in perlite terrariums with heat cables and long LED strip Lights.
one (or more) clear plastic box(es). Mine is 70 litres (A clear cover is required to allow light in when the lid is on. It should be obvious but I will say it just in case: Do not drill the base of the box for drainage 🙂 we’re building a terrarium and they need no drainage)
A heat cable(the type used in hot bed propagators or reptile terrariums. A short one (3 metres) should be sufficient for just one box. Add 2 meters for every extra box.
A 12cm layer of perlite in each box is recommended. This works great in the sense that I don’t need add water very regularly.
- This box should probably NOT be placed by a south facing or east facing window as direct sunlight can create very high temperatures within which will cause all the cuttings to be cooked if you forget to water and id there’s enough ventilation in place. It’s achievable but it’s dangerous if the ventilation is not adjusted between sunny and cold weather days. North facing windows are safe –as is any room, with the aid of artificial lighting.
2. Heat cables come with warnings. So be sensible! It’s not impossible for fires or electric shock to occur if these devices get damaged. So, It’s safer if the heat cable never sits in water or in direct contact with the box. I have several of these and never experienced any fires or shocks.
The lid will have to be perforated so that there’s sufficient air flowing out. Don’t use a drill as it might crack the lid; rather, use a hot iron bar to burn holes in. I did this part in my kitchen, warming up the iron bar on the cooker. A vile smell of plastic fumes hung in the air afterwards –complaints of those I live with also RUNG in my ears for even longer, so be warned 🙂
When you’ve assembled the box(es) with a 12 cm layer of moist perlite, perforated the lid with 8 or more holes, placed the box where it will live; placed the heat cable underneath it (with a bit of card board or something else in between); turned it on :-); After 60 minutes or so, it’s now time to use a thermometer to measure the temperature within. 22C to 27C is what I recommend. Monitor the temperature for a couple of hours. If the temperature is too high, then use a timer to turn the heat source on and off on intervals. During the summer, my heat cables are turned on and off every 30 minutes. Some people use a thermostat which, I guess, can be even more effective but I don’t use those as a timer will do similar. Either way, ensure there’s a temperature range mentioned above. Adjustments will likely be needed come winter or summer. So don’t forget this detail.
Although having artificial light is not altogether essential, it’s highly recommended. My artificial lights(cool-white LED striping) stay on 18 hours every day!
Once you know the temperature in the box is in the above range, is time to plant your cuttings in 🙂
If you like rooting your plants in very high humidity, be careful with suculent hoyas like Pachyclada and Kerrii –The cut must be healed BEFORE planting them in this sort of arrangement.
You might ask: what happens once I see that it has roots? Is this the moment to move them to soil.
Roots will keep developing while the cutting is in the perlite. Ideally, cuttings should only be moved to soil once you see new growth forming. That means that the roots are during enough, or SO STRONG, that the cutting begun growing. Roots precede growth!