My early-bearing black raspberries have finished fruiting for the season. As summer advances, they’ve been putting much of their energy into growing new branches for next year’s crop. This new growth is long and thin, stretching far beyond the parent plant’s initial location.
The new branches grow so long, in fact, that they eventually bend down to the soil line. Once the tips of these new berry canes make contact with soil, they’ll eventually root to form a new berry plant.
This is just one of the many ways that brambles naturally multiply. And, as it happens, you can easily take advantage of this process and put it to work for you.
Raspberries Propagate Via an Asexual Process
You may be used to starting most plants from seeds. For their part, seeds are the result of successful pollination of the plant’s flowers. Unlike that process, this kind of plant propagation is asexual.
In other words? Male and female flower parts don’t play a role when you propagate black raspberries.
Instead, extra plants are propagated from the vegetative parts of existing plants. For both tip layering and simple layering, you’ll use existing plant stems and leaves to propagate more of the same.
Incidentally, raspberries, blackberries and other types of brambles aren’t the only plants that respond well to this kind of asexual propagation. It works with woody shrubs like witch hazel, magnolias, and forsythia bushes, too.
Want to give it a try? First, make sure you won’t run afoul of any plant patent laws along the way.
Getting Started with Propagating
Rather than start my new plants directly into nearby ground, I like to use individual pots when soil layering brambles. This provides me with many more options once the new plants take root. For instance, when I propagate black raspberries, I can more easily give the extras away or decide to start a whole new berry patch elsewhere.
You’ll need these items for your own tip layering project:
- some large pots
- a mix of potting soil and mature compost or worm castings
- landscaping pins
Step by Step
Fill one of the pots with your amended soil mix and water well. Next, choose a healthy new branch—not one of your old canes which has already fruited. Locate the very end of the branch.
If you look closely, you might already notice the beginning of root growth here.
If you see that roots have already started to sprout at the tip, simply pinch off a few sets of nearby leaves. (See step 1 in image below.) Be careful not to damage or remove any of the fine root hairs which also may be present here.
You should be left with 2 to 3 inches of bare stem with some roots at the very tip. (See step 2.) Bury this entire section in your soil-filled pot and water thoroughly. (Steps 3 and 4.)
To make sure the branch tip remains planted in the pot, use a landscaping pin to secure it at the soil line. (Step 5.) Meanwhile, the rest of the branch will remain tethered to its parent plant. (See Step 6.)
Keep the potted branch portion moist. Over the next few months, healthy roots and new plant growth will develop. (If need be, you can partially bury the pot to help insulate it during colder weather.)
Finally, with a quick snip, you’ll eventually separate the potted branch from the parent plant.
Propagate Raspberries with Simple Soil Layering
Let’s say you’ve located a healthy new branch that doesn’t appear to have any root activity along its tip. In that case, you’ll leave the last 3 or 4 inches of the branch’s leaves intact. Now, carefully pinch off nearby leaf sets within just the next inch or two.
Using your fingernail or a clean, sharp knife, make a shallow scrape along the underside of this leafless stem portion. Use a landscaping pin to push this section of stem against the moist soil in your pot.
Don’t be afraid to bend the stem slightly with this step when you propagate black raspberries. Small wounds and bends in bramble branches will help to spur rooting.
Now, bury just the pinned section with a little more soil and water well. Ultimately, you’ll want both the leafy branch tip and the rest of the tethered branch to remain above the soil line. Once healthy roots and new plant growth have developed, you can separate the potted branch from the parent plant.