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How to propagate houseplant cuttings using the propagation sphagnum moss box method! How to root any houseplant FAST!
It goes without saying that you’ll need some sort of container to use for propagating plants.
You can purchase propagation trays specifically made for propagating plants, or you can make your own. My favorite way to propagate plants is using my own DIY plant propagation box
A plant propagation box, or propagation chamber, is something that can be used for rooting plant cuttings.
It works like a mini greenhouse that will protect plant cuttings and give them enough moisture so they can survive until they sprout roots.
Here’s a DIY propagation box tutorial. In this video I’ll show you how to make a propagation box for plant cuttings that includes a grow light so you can propagate plants under ideal conditions any time of year or in any room of your home.
For a more information about plant propagation read our complete plant propagation guide here.
Make your own DIY propagation box
A propagation box is an essential tool for propagating plants, and it makes the process go much faster. Most types of plant cuttings can be easily rooted using a propagation box. You can purchase commercial propagation trays specifically made for propagating plants, or you can make your own propagation box.
Total Time: 2 hours
Make the propagation box
Find or purchase a clear plastic storage box with a lid. You can also use a glass fish aquarium with a hood if you have one on hand.
The size of the box doesn’t matter too much, but think about what types of cuttings you will be rooting in there and how tall the box will need to be.
The plastic storage box I use is about 16”W x 10”D x 10”H, which is perfect for most cuttings.
Add propagation soil
Add your propagation soil to the box, and spread it evenly over the bottom of the box.
The soil should be about 3-4 inches deep. It’s important to use propagation soil (rather than potting soil) inside a propagation box to ensure success.
Add water to wet down the propagation soil. Keep the soil moist but not soggy, and never allow it to dry out completely.
If you added too much water to your propagation box, you can simply leave the lid off the box for a day or two to allow the excess water to evaporate.
Add the plant cuttings
You can root just about any type of plant cutting in this propagation box, so I encourage you to experiment!
Whenever I trim a plant or a piece breaks off, I’ll put the cutting into my propagation box.
For best results, dip the cut end of your plant cutting into rooting hormone before sticking it into the propagation soil.
Make a hole in the soil with your finger and place the cutting into the hole so the rooting hormone doesn’t rub off.
Lightly pack the soil around the stem of the cutting to ensure the medium is touching the cutting.
At least one leaf node should be below the soil line.
Make sure that none of the leaves are below the soil, and pinch off any leaves that are laying on the surface of the soil.
Put the lid on the box
Put the lid on your propagation box. If the lid on the storage container is airtight, poke some holes in the lid or prop it open slightly to allow air to circulate in the box.
Air circulation helps prevent mildew growth in the propagation box. I like to use an electric drill with a small-medium sized drill bit to drill holes in plastic lids because some types of plastic will crack if you try to make holes with a hammer and a nail.
Drill the holes 2-3 inches apart on the lid.
Where to put your propagation box
Place your propagation box in an area near a sunny window inside the house. If you don’t have a sunny room to put it in, place a plant grow light above the top of the box. It’s best to keep your propagation box inside the house to keep it protected from wind, rain, bugs and too much sun. But, if you must put it outside, it should be kept in the shade and protected from rain so it doesn’t get overwatered. Inside or out, always keep your propagation box out of direct sunlight.
Add bottom heat (optional)
Use bottom heat to help speed up the rooting process. You can add bottom heat by placing your propagation box on a heat mat (the same one you use for your seedling trays). During the winter, you can place your propagation box on or near a heat vent (be careful if it’s near a vent, because the dry air from the heat vent will cause the soil in your propagation box to dry out faster).
Check on your propagation box every few days to see if there are any new roots.
Soft stem cuttings will root in about three weeks (some will root in as little as few days), and hardwood cuttings will take about 8-10 weeks.
You’ll also want to monitor the humidity level inside the box, and the moisture level of the propagation soil. The soil should never be soggy or completely dried out, it’s best to keep the soil consistently moist. To water your propagation box, use a gentle spray from the kitchen sink sprayer or a plant mister; you don’t want to disturb the propagation soil once your cuttings are in the box.
- Clear plastic storage box with a lid, or a glass fish aquarium with a hood
- General purpose propagation soil (see recipe on p. 15)
- Rooting hormone
- Heat mat (optional)
- Plant grow light (optional)
- Clippers or knife