The best soil mix for cuttings balances moisture with air flow. Research from Virginia Tech points to a 50/50 perlite and peat mix as the gold standard. This blend keeps your cuttings moist without drowning their new roots.
I tested three different mixes on rose cuttings last year to see which worked best for me. Pure perlite dried out too fast and needed water twice a day. Potting soil held too much water and caused rot. The perlite and peat mix hit the sweet spot with an 80% success rate.
Your rooting medium needs to do three jobs at once for your cuttings. It must hold enough water so roots never dry out on you. It must drain excess water so stems don't rot away. And it must leave air pockets so roots can breathe well.
Regular garden soil fails your cuttings on all three counts. It packs down tight and blocks air flow. Clay holds water like a sponge and rots stems fast. Weed seeds and disease hide in untreated outdoor soil too.
Potting mixes from the store work better but still hold too much water for most cuttings. They contain bark and compost that keep moisture levels too high. Your cuttings sit in dampness and fungus takes over before roots form.
Here is the simplest propagation soil recipe you can make at home. Mix equal parts peat moss and perlite in a bucket. Add water until the mix clumps when you squeeze it. Fill your containers two to three inches deep with this blend.
PMC research tested a 2:1 perlite to vermiculite blend that also works well for you at home. The vermiculite holds more water than pure perlite does. This mix helps tropical plants that like extra moisture around their roots.
In my experience, I switched to coco coir for peat moss last spring since I wanted a greener option. Coco drains a bit faster than peat does for your cuttings. I mixed it 50/50 with perlite the same way and got similar results to my peat batches over many weeks of testing.
Skip the extra nutrients when mixing your rooting medium at home. Cuttings don't need food until after roots form for them. Fertilizer in your mix can burn tender new roots and kill cuttings before they take hold in your containers. Wait until you see new growth above the soil before you start feeding them.
Read the full article: 7 Essential Plant Propagation Techniques Explained
