How to propagate plants at home

A couple of years ago, my neighbour was showing me the Cuban oregano growing in his garden, and broke off a little sprig so I could sniff the minty, camphor scent. He told me to plant it. So I stuck it in a glass of water to root, it eventually graduated to a little pot filled with soil, and it's been a houseplant living in my kitchen windowsill ever since. Growing new plants from a variety of sources, like cuttings, is called plant propagation. It may seem like something only experienced green thumbs should attempt, but it's quite easy, and a great way to make more houseplants. 

"Everyone needs more nature indoors," says certified professional horticulturist and author Leslie Halleck. "Propagating from your plants is desirable if you want to save an old houseplant that may be in decline, replicate a plant that has been in your family for many years or even generations, give green gifts to your friends and family, and super-stretch your gardening and houseplant budget."

Besides witnessing the magic of plant biology unfold in his home, Darryl Cheng, author of The New Plant Parent and creator of House Plant Journal uses a Harry Potter reference to describe the allure of replicating plants: "I also like to think of propagation as a 'horticultural horcrux', where I can clone my favourite plants, so even if the original dies, it lives on through its propagation." 

The best part of this little houseplant DIY is that you don't need many tools to get started. Sharp, clean pruning shears or garden snips will do to take your cuttings (clean, sharp scissors will do in a pinch), as well as clean glass jars filled with water. Cheng will use soft wire ties to bundle a few cuttings together and to keep them held at the edge of the jar (preventing them from falling right in). 

"Do your research to understand the method of propagation that will work best for the specific type of plant," suggests Cheng, who loves to collect snake plants. "Some plants are best propagated by root division, stem cutting, leaf cutting or air layering."

The easiest plants to propagate

Halleck recommends any plant that produces plantlets or pups that can simply be cut away from the mother plant, like the classic spider plant, as great beginner-friendly options. All you have to do is snip the small plantlets at the end of the flower stems, which come complete with an initial root system and shoots, and root them in water or potting soil. "Pothos ivy is right there with spider plants," she adds "Just snip off a piece of the stem with a few nodes (the joint where the leaf attaches to the stem), and drop it in a glass of water. It will root in no time and you can pot up a new plant within weeks!"

Other recommendations include plants that grow in clumps, like snake plant, because you can easily divide them at the roots to make several new plants. "And succulents, like sedum and echeveria, will root easily from whole leaves resting on the soil surface," says Halleck.

Once plants in water have developed their roots, you can move them into small three- to four-inch pots filled with a lightweight indoor potting mix.

Be aware of plant placement

Our homes do not always present the most optimal growing environment for houseplants — they're not equipped to mimic a tropical or greenhouse setting, especially here in Canada. Windowsills and some rooms can get especially chilly in winter, and central air conditioning can create pretty dry conditions, so avoid setting your plant in extreme conditions. You also need to make sure your plant will get lots of natural light after they take root — houseplant cuttings don't need much light during the rooting process, Halleck points out. "Once the cuttings have rooted and begin to grow new foliage, you'll need to move your new plants to normal light conditions for that particular species," she says. A quick internet search can reveal the type of environment your plant prefers.

Dos and don'ts 

Hallack has these best practices to offer. Follow them for plant propagating success!

• If you are water-rooting your cuttings, do be sure to change the water weekly to keep it fresh. 

• If you're not water-rooting, do use a soilless medium for plant cuttings, such as coir, sphagnum moss, Oasis rooting cubes or rockwool, as the microbes in organic soils can cause your plant cuttings to rot before they root.  

• Don't take cuttings from houseplants that are obviously diseased or have an active pest infestation, especially if you plan to give your cuttings or rooted plants away to others.

• Don't leave your cuttings too long in water or a rooting medium after they've rooted; once the cutting has started to side-branch in the water, or the roots grow to the bottom of your soilless rooting medium, it's time to transplant your cutting.

• Don't propagate patented plants for sharing or selling. You can check the plant tag for a patent ID and if you see one, you are not allowed to propagate that plant to give away to others or to sell, but you may be allowed to propagate it for your own home. 

Tara Nolan is a co-founder of Savvy Gardening (https://savvygardening.com/) and the author of Gardening Your Front Yard and Raised Bed Revolution.