June 6, 2021
I get a lot of questions about what kind of lighting, or how much, is needed for plant propagation. While dive into this topic in my book Plant Parenting, I also review propagating tiny plants in my new book Tiny Plants. While the basic principles for propagating many different types of tropical plants are similar, I do employ some slightly different tactics when propagating my most itty bitty houseplants.
In the photo you'll see some vegetative propagation and new transplant areas I have under grow lights. Some of the plants here are in the genera Sinningia, Begonia, Masdevallia, Peperomia, etc. and some new bareroot Lithops spp. just potted up (which should be in a shaded area for a week or two).
Here I have a s 24" 4-lamp T5 fixture that I've fitted with just one 24W HOT5 fluorescent lamp, for lower light cuttings and species that are rooting. Directly under the lamp the plants with some active root growth are getting a DLI of about 5 umol/m2/day - measured with quantum flux meter and PPFD- putting the output in a shade/heavy shade low-light category; which is perfect for cuttings or other low light species that are transitioning. At the outer edge of the fixture and the lamp, it’s about a 2.5-3 umol/m2/day DLI for cuttings with no roots yet (cuttings need less light before they've started rooting). This lamp is on for 12-hrs (to hit the DLI ranges I listed above).
You could do the same with an LED bar lamp or HOT5 retrofit LED - although a lower wattage LED would typically do the same job 18-20W range would do the job nicely and you could probably leave the LED on for less time to achieve the same DLI (depending on it's actual PPF - output potential of PAR).
Most importantly...aren't they so CUTE???
If you'd love to learn more about growing and propagating tiny plants, be sure to check out my new book TINY PLANTS!