Get more rex begonias
What if I told you that you could propagate a bunch of beautiful rex begonias for almost nothing? It isn’t too good to be true! These elegant plants aren’t hard to propagate. I like to take leaf cuttings because it’s so fascinating to watch a single leaf sprout a whole bunch of babies. Let me show you the secret to propagating rex begonias from leaf cuttings. If you grow cane or wing begonias, give this technique a try with them, as well!
Materials & tools
- Scissors or pruners
- Sharp pocket knife or razor blade, or Xacto knife
- Small 5 inch pots or a shallow nursery tray with a lid
- Plastic wrap
- Soilless seed-starting mix
- T-pins (commonly found at office supply stores)
- Small stones (3-5 per leaf cutting)
- Fluorescent lights (optional)
- Seedling heat mat(optional)
- 3-inch pots for transplants
Step 1: Prepare the supplies for propagating rex begonias
Gather the items on the "Materials & Tools" list above. To be cautious, I always rinse all my supplies (and my hands) in a solution of 1 teaspoon bleach to 1 quart of water. Begonias are prone to fungal infections, and bleach kills any lurkers. Fill the tray with damp potting mix and you’re ready for the fun part — taking the cuttings!
Step 2: Take a leaf cutting from your rex begonia
Look for a healthy, full-grown leaf on the parent rex begonia plant. It can be a tattered, older leaf, but on the underside, the main veins should be plump and undamaged. Cut the leaf and stem from the main plant, then take off the leaf stem and throw it away so you’re left with just the leaf.
Step 3: Make cuts in the rex begonia leaf
Flip the begonia leaf over and make a ½-inch cut across five or six of the largest veins with your knife. I’ve cut each vein about an inch from the central vein in the photo above. These cuts (and the stem cut) are where the new plantlets will form.
Step 4: Pin the rex begonia leaf into seed-starting mix
Turn the begonia leaf back over and press it into the seed-starting mix. Then, to keep the cuts in contact with the mix, start pushing T-pins through the leaf into the soil. Use as many as you need to hold the leaf flat. Avoid putting a pin through a main leaf vein, or that vein may not root.
Keep things in place
A few stones may help keep the begonia leaf from curling up and away from the mix, as well. Leave them in place until they start to get in the way. Start as many leaves as will fit in your tray or pot without the leaves touching.
Step 5: Provide humidity and light for the begonia leaf cutting
Cover your container with its dome or plastic wrap. But be careful not to let the plastic touch the leaves or you could risk fungal problems. Keep your leaf cutting near 70 degrees and give it plenty of humidity. I mist mine daily and water the soil once a week.
Give them light
I hang fluorescent lights 6 inches above the cuttings and leave them on about 12 hours each day until the new plants start to grow. You could also put your leaf cuttings in an east window as long as the temperature stays consistently warm. If you have a heat mat for seedlings, that will help the begonia leaf cuttings get off to a faster start. Keep the temperature setting at about 70 degrees.
Step 6: Watch for new growth on your rex begonia leaf cutting
See those tiny plants unfurling? Expect one or two plants per cut. They can take up to 6 weeks to emerge, so be patient.
- When the plants are 3 inches tall and have at least two leaves, they’re ready to lift. The original leaf probably will have torn apart and may have even disintegrated.
- Gently transplant the babies into 3-inch pots.
- Grow them there until they’re big enough to put in the garden or transplant into more permanent pots.