Cuttings for Propagation
Build a simple propagation box to house your cuttings and help them thrive.
When my mother, Beatrice, passed away, I inherited a small, struggling Christmas cactus that was barely clinging to life. It was little more than a handful of scales on two branches. The poor thing had been left in a back room, largely forgotten during her lingering illness. But five years later, this plant has recovered, growing to easily four times in size, if not more.
Even before it came into my care, this plant was a treasured family heirloom, belonging first to my paternal grandmother, Laura Weidman. I can remember a time when it spread an easy 2 feet in width, filling its pot with arching falls of leaves and blooms.
Now, the time has come to take cuttings of this treasured Christmas cactus for family members, to ensure it lives on as a legacy to first Laura, then Beatrice. No pressure.
Propagating new plants by rooting cuttings seems to defy logic: Break off a chunk of plant, stick it in dirt, and expect it not just to live, but also to grow new roots and become a new plant all its own. That might sound as unrealistic as cutting off your own pinky finger and growing a new one, and then expecting the severed finger to grow a whole new “you.” Impossible!
But gardeners do exactly that (with their plants, not their pinkies!) all the time. At least, some do. The rest of us envy their arcane green-thumb magic.
What if I told you that magic could be yours? It can, and it won’t cost you an arm and a leg. Or even a pinky.
It all starts with a simple piece of equipment: a propagation box, sometimes called a “rooting case.” A propagation box is an enclosed space designed to hold rooting media (potting mix, sphagnum, sand, perlite, etc.) and cuttings while maintaining high humidity. Its purpose is to keep the cuttings alive and hydrated long enough to grow new roots.
The supplies required are inexpensive and easy to find: three plastic shoeboxes, potting materials, and your cuttings. You can find the boxes at most department stores, big-box home improvement stores, or even office supply stores. Any style of box will serve, as long as it’s clear or translucent plastic, but nesting boxes with sloping sides work best. You’ll also need to be able to flip one box upside-down and securely set it on another one as a lid.
Image Andrew Weidman
Drill or punch 3/8-inch drainage holes in the bottom of one box. The hole size isn’t critical; they just need to be large enough to let excess water out while keeping the rooting material inside. Different plastics have different characteristics, including how well they cut and drill. The first time I tried drilling holes into a shoebox, I turned the box upside-down to drill in from the bottom. The unsupported plastic shattered out in a much bigger hole than I’d planned on making. I drilled the next hole from inside the box, into a supporting piece of scrap wood. That hole didn’t shatter.
Image Andrew Weidman
Nest the drilled box into the undrilled box. This undrilled box will serve as a catch basin for drainage water, protecting the roots from rotting and the table or shelf from water damage. If your boxes don’t nest together, use a slightly larger box for the bottom catch basin.
Image Andrew Weidman
Fill the inner box with moistened rooting material. This can be potting mix, milled sphagnum moss (“peat moss”), coir, sharp (“builder’s”) sand, or perlite. Don’t use garden soil: it’s too heavy and dense, and it’s teeming with bacteria, fungal spores, and weed seeds.
Image Andrew Weidman
Stick your prepared cuttings into the rooting medium. Push each cutting into the medium to about half its length. It’s OK to push the cutting in so far it touches the bottom. Don’t be afraid to really pack them in, even as close as an inch or so apart. Really fill the box with cuttings. Not all of them will root and survive, and if you have extras, you can always share them with friends.
Image Andrew Weidman
Flip the last box upside-down, and set it on top like a tent. You may need to secure it in place with a pair of large metal spring clips, depending on its stability. Label the case with the cuttings’ variety and the date. You can use whatever marking style you prefer, as long as it’s reasonably waterproof and won’t fade over time. I like to use a permanent marker on masking tape, placed on the side of the inner bottom box, so it stays with the cuttings until they’re ready to be potted.
Set the propagating case under plant lights in a place where it will be undisturbed for several months while the cuttings root.
That’s it; that’s all there is to it. Making a propagating case can be as simple or as complicated as you’d like. Why not keep it simple?
Here are some things you can do to increase your chances for success:
Start a lot more cuttings than you need. Not all of them will root, for reasons you won’t always be able to see. You may not need all the plants that do root successfully, but too many plants is a good problem to have.
Preserve your sanity by filling each case with only one kind of cutting, especially one variety of a single species. Don’t trust your memory! Sure, you know exactly what each one is now. I guarantee that five minutes after you’re done, you won’t know what’s what. I can’t tell you how many times I’ve shared “mystery” plants with friends, telling them it could be this, or it could be that. Or it could be something else entirely!
Keep Their Toes Warm
Cover the surface of the rooting medium with a thin layer of milled sphagnum or perlite. This will help prevent the spread of fungal diseases and other problems.
Image Andrew Weidman
Cuttings love bottom heat. Last fall, I boxed up a case full of fig cuttings and set them in my basement nursery area to root under fluorescent lights. Most of the cuttings pushed leaves, but few produced roots, and they languished, slowly fading away over the next two months. I started a second case and set that one beside the first, but with this one, I remembered to include a soil-heating mat for starting seedlings. The average temperature in the basement is somewhere in the mid-50s, a bit chilly for rooting cuttings. The difference between the two cases was astounding: Each case began with about 16 cuttings. The case with bottom heat rooted 10 successfully. The unheated case? Just one cutting rooted. That’s not a good rate of return by any standard, even if I only needed one new plant.
Cuttings also love moisture, but not too much of it. Too much water leads to root rot; too little leads to dried-out, dead cuttings. The perfect balance will keep your cuttings plump and healthy, and if it’s a little on the dry side, will even encourage more rapid root growth. When you set up your case, moisten the medium to about the dampness of a wrung-out sponge. Potting mix, coir, and sphagnum should form a loose, crumbly ball when squeezed together in your fist, but you shouldn’t be able to squeeze any water out of it. Sand and perlite can be harder to judge, but you’ll want to avoid having excess water running out of it.
With those tips in mind, let’s discuss some common propagation practices. Why not just root in water? After all, lots of people do it with snapped-off houseplant pieces, and many plants will strike roots in water. The problem is that, in most cases, water roots aren’t the same as soil roots. They’re used to a completely different environment and a completely different set of conditions. Drifting around dreamily in water is vastly different from pushing your way through soil – even light, fluffy potting mix. So newly potted water-rooted plants might die.
Many gardeners swear by watering their cuttings with willow water. Willow water is made by soaking cut-up stems of weeping willow, black willow, or pussy willow in water, or by actually rooting willow cuttings in water. The theory is that willows possess sky-high levels of natural rooting hormones. Anyone who has ever started a willow fence or put a bouquet of pussy willows in a water-filled vase knows the truth in that statement. I’ve used willow water in the past, and I’ve had success – at rooting willows. I’ve never seen any difference in using willow water on other cuttings.
There are also other store-bought rooting hormone options, some in a powdered form in a talcum powder base, and others in a gel base. I’ve tried both, and I’ve had more success with gel than with powder, but neither gave that much more success than when I skipped the rooting compound.
They Are All Individuals
No matter how you propagate, understand that every plant has its own preferred conditions for rooting. Some, like willows, just need to fall in the dirt. Others, like cacti, need to dry in the air for a few days before being potted up in drier soil. Figs root best as dormant hardwood cuttings; gooseberries as midsummer semi-hardwood. Knowing each plant’s special needs can feel like a magic all its own. Get a good reference manual on plant propagation; I rely on Plants-a-Plenty by Catharine Osgood Foster, and The American Horticultural Society’s Plant Propagation, edited by Alan Toogood.
Finally, the most overlooked condition for rooting success is the need for patience. Rooting cuttings takes time, often measured in months. Resist the urge to tug on your cuttings to see if they’re rooting. Too much movement can destroy tender new roots before they have a chance to grow. Don’t be in a hurry to open up the case, either. I’ve watched entire cases of luxuriously growing figs wither and die in a day’s time because I impatiently opened the case before they had formed sufficient roots for supplying the moisture they needed. Remember, the case works by maintaining high humidity so the tops don’t dehydrate.
Image Andrew Weidman
You can get an idea of when to open the case by watching the sides of the lower box. When you can see lots of roots showing, you can start opening the case for a little bit each day, much like hardening off vegetable transplant seedlings. Start with 10 minutes or so at a time, and increase the open time by 5 minutes or so every few days. For plants destined for outside planting, you can later remove the outer drainage well and set the inner box in a shaded spot for late spring into summer before potting them up or planting them in fall. Just remember to water them daily during dry weather, as you would any other potted plant.
Follow these steps to build your own case, and with a little research and a healthy helping of patience, you’ll soon be rooting your own cuttings. Remember, plants really do want to live. Sometimes, their will to live amazes me. Once, I found a bundle of rose cuttings I had left wrapped in damp newsprint weeks earlier, The paper had dried almost completely, but the cuttings were still alive – and even had half-inch roots forming at their base. Ten years later, one of those rose cuttings gives me roses of its own each summer.
And my mom’s Christmas cactus? Two months after I stuck 17 cuttings of it in my case, I have 17 happy little plants growing, which is more than enough to share with family. Beatrice and Laura’s Christmas cactus will live on, thanks to an easy-to-make propagating case.
Andrew Weidman lives and writes in Lebanon, Pennsylvania. He’s been practicing his own brand of garden magic for years, propagating more plants than he could ever find places to plant them. Thankfully, friends, family, and the Backyard Fruit Growers are more than happy to adopt the extra plants he starts.
The Plant Propagator’s Bible
With easy-to-follow, step-by-step instructions, veteran horticulture teacher Miranda Smith provides a complete reference showing every step for cultivating new plants – whether from seed or cuttings, or with techniques such as layering, grafting, and budding. Smith teaches readers, with the support of hundreds of color photos and detailed illustrations, the natural process and conditions in which plants grow and reproduce. The Plant Propagator’s Bible offers guidance for expert gardeners, but is also a perfect primer for the novice plant lover and horticulturist.
This title is available at the Grit store or by calling 866-803-7096. Item #10941.
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