Plant Propagation Methods

November 20, 2016

Plant Propagation Methods

LAYERING

Layering is a method of propagation used on woody-stemmed herbs like upright thyme, lavender, sage, rosemary, winter savory, tarragon, and the southernwoods. This is by no means a "speedy" way to get new plants. This method has a very long "satisfaction" period, so you need to plan for this in advance and get it done as early as possible. Do this early in the spring, as soon as the fear of frost has passed. This way, by the end of summer, you have new plants to plant in the garden that will establish themselves during the fall and winter and future growing seasons.

To layer a plant, take a healthy outside stem and bend it away from the parent plant. Make sure the soil where you are pulling the stem to is enriched. "Wound" the stem by making a notch or rubbing the bark and under-bark off with a dull knife. Anchor the stem in the ground with a piece of heavy wire that has been bent in half or use a clothespin. Make sure you leave at least 6 inches of the branch exposed to the air. Cover with soil and then place a brick or heavy stone on top, to prevent the soil from being washed or blown away. After two or three months (possibly a bit longer), the branch will have rooted, creating a new plant, or plants, that can be cut from the parent and planted.

This method gets you the new baby plants, but also saves the parent as it is not affected when you clip away the new babies.

STOOLING

Another method of layering is known as "stooling", "mounding", or "stool layering". This type of layering is great for reviving unruly, spindly and aging lavenders, or any other bushy, woody herb that has become leggy and rough-looking. This procedure will ultimately kill the parent plant, but you will have lots of babies to take its place.

Mound up the soil around the center of the plant, burying the center branches. If rain washes the soil away, replace it right away. Leave it this way for about two or three months. At the end of the time period, dig up the parent plant. Roots will have formed all over the buried branches. Any pieces with a few leaves and healthy roots can be cut off to be replanted into pots or directly into beds. This gives you a bunch of new offspring, genetically identical to the parent, so you won't miss the original one!

Stool Layering

Division by Hand

DIVISION

Division is simply uprooting the plant, being careful not to harm the roots. The original plant is then separated by pulling it apart or slicing down through it, into two or three sections (divided). Then, the new pieces are transplanted into their new locations. They should continue to grow and behave much in the same way the parent plant did, since they are actual portions of that original plant and genetically identical to it. Plants should be divided in the spring for best results.

Division Using a Knife

SEED PROPAGATION

Many herbs, like lavender, are rarely started from seed, due to an extremely long germination period. Additionally, some herbs don't always produce seeds because some hybrids are "mules", or sterile. Your best bet for propagating most herbs, especially woody ones like lavender and rosemary is, instead, through cuttings.

CUTTINGS

Propagation from cuttings is my favorite method for obtaining new plants. I prefer to start them in a small vase of water, with no soil at all. This is otherwise known as growing them hydroponically. You may use soil if you prefer. These cuttings, measuring 2 to 3 inches long, are taken in the summertime from side shoots. These shoots should be from the growth of one season and may include some older wood at the base.

Propagation by cuttings, in the case of woody herbs (here I mean ALL woody plants, not just the ones we use for seasoning and medicine), can be a very long-term project. Some tender herbs (non-woody ones), like ivy or pothos, are fast growing plants anyway. If you take cuttings of these, and are trying to grow them in water only, you will see new roots forming in the vase after only a day or two. After two weeks, there will be so many roots that you will wonder how there is any room left for water!

This is not, however, the case for woody stemmed herbs. In early June 2015, I snipped an awkward stem off a rosemary plant we had just purchased. I put it in a little vase with water and I started to wait with bated breath to see what it would do. And it did -- nothing. It just stayed very nice and green and healthy-looking, so I left it alone.

Sometime around October, I noticed there were some tiny new leaves at the top of the sprig and at some of the groups of leaves along the stem. I was excited because it meant that at least the little stem wasn't dead or dying.

One morning in December, close to Christmas, I looked over at my little plant, as I did most days. This time, much to my surprise, there was a tiny one-inch bit of a root sticking out of the bottom of the stem! I swear it grew overnight! Well, overnight and 6 months.

The same thing had happened with a lavender sprig I got from my neighbor's bush. It, too, took around 6 months before it sent down a root. It seems the woodier plants start to grow from the top first, before sending out roots, based on my own observation. Be patient. From what I have read, a six-month wait is fairly typical for rooting most woody-stemmed plants.

I never transplanted either of those shoots into the garden, but by the time we moved in Aug of 2017, each one had had enough top growth that I was able to snip off bits of those and start more new plants. I was lucky enough to be able to do this on two separate occasions for each of the rosemary and lavender sprigs. All six new plants were thriving in their little vases when I had to dump them out because they would never have withstood the heat during the move. I was so sad about it! It was almost like dumping some of my own children! After all, I had raised them from nothing and then kept careful watch over them for the preceding two years. How heart-breaking!

A photo of my "baby" Rosemary is shown below.

My Baby Rosemary--Cutting Rooted in Water

To take a cutting, grasp a healthy shoot and pull it downward so that a piece of the older wood comes with it. Cut the branch from the original plant by making an angled cut. This allows the cutting to soak up more water and nutrients and form roots slightly faster. Then place these cuttings 3 to 4 inches apart in moist sandy soil. When these cuttings have been growing for a year, they can be planted out 4 to 6 feet apart in dry, light, stony or gravelly soil that is not subject to frost. The same is true of those grown hydroponically, too.

This isn't my cutting garden, but I love her use of ordinary old bottles and jars as rooting vases. I'm going to start saving old bottles to do this for myself!

For more tender herbs and ones that don't become very woody, like thyme or oregano, you can also take cuttings, but a slightly different method for starting them is required. To do this, take 3-inch pieces from established plants. You should only use the new green growth, not woody older growth. Place the cuttings in wet sand and keep it moist for two weeks until new roots appear. You will know they have rooted because they will resist a gentle tug and should show new top growth, too. Don't go tugging on them for at least two weeks, though, so as not to disturb them. You don't want to break any of the tiny nodules where the new roots will form. Once the roots have grown, they can be transplanted to new pots or into the garden.

There are several more methods of propagation that are used for gardening. I will add more as time allows, but I believe this should be enough to get you started on your way to a full and lush herb garden.

I hope this is helpful to you and you discover how easy it is to grow your own herbs and that you will eventually have bucket loads of new FREE baby plants!

Let me know how things are working out for you!

Peace and Love Always,