Want more Flowers? Pinch & Propagate.

Growing flowers is a labor of love. I spend hours planting seeds, watching perennials wake up, and dreaming of the explosion of blooms to come. Yet, with all of that work, the goal is to have as many flowers as possible. Scouring the internet and books for ideas results in one recurring theme: pinching. I've been using this technique for years and have seen firsthand how effective it is.

 

Pinching is the simple process of removing the growing tips of young plants to encourage them to branch out and grow more flowers. It's straightforward to do and requires no special tools most of the time. That's where the name pinching comes from. You literally use your fingernails to "pinch" out the tops of plants. What pinching does is disrupts something called apical dominance. Plants left to their own devices will grow a central stalk first before branching out. So while our goal as gardeners is to get the most out of a plant, the plant's goal is to produce seed a.s.a.p.

 

Let's look at snapdragons, for instance. If you grew a snapdragon from seed and left it alone, it would grow tall and produce very few flowers, go to seed, and then go dormant. From a plant's perspective, that would be a complete success. But we want more out of that snapdragon. We want a bushy plant with lots of flowers to fill out our garden beds with blooms and beauty. When you remove the growing tip from a plant, it sends a distress call to all of the backup buds in the leaf axils, telling them to GROW NOW!!! Now, instead of one main stem, the plant has to divide its energy between the side buds. The result? The stems are thinner (sometimes shorter), and you multiply the number of blooms. And in the case of herbs like basil, thyme, and lavender, harvesting tender pinched tips instead of taking deep mature cuts will result in a bushier, less woody, and compact growth habit. Those tender tops taste better too.

 

The best time to pinch a plant depends on the plant you're pinching. But a general guide is to think about how many branches you want your plant to have. The more leaf nodes you have, the more dormant buds you have that will branch. I pinch sweet peas when they have three to five leaves and pinch them down to two or three. I let snapdragons grow 4-6 sets of leaves or nodes before pinching, and the same with dahlias. And if you compared how tall those two plants are when they each have 4-6 nodes, you'd see going by height isn't the right way to think about it. Snapdragons have a very compact form and can grow six nodes when they're only 5" tall. A dahlia will likely be closer to 8-12" when it has 4-6 nodes. So, keep that in mind. Look for nodes, not for height.

 

Now that you have all of those pinched tips let's talk about propagation. Yes! There are many, many, many plants that you can pinch the tips of and then propagate into more plants! So pinching not only results in more flowers on the original plant, but pinching can even result in FREE PLANTS! When taken early in the season, these tips have the time and potential to catch up to their seed-grown counterpart and perform amazingly.

 

Why would propagating tip cuttings be useful? What if you only had one seed of your chocolate cosmos germinate, and you were hoping for ten? Propagate! What if your friend gave you a single Penhill Watermelon dahlia, and you want to grow a whole patch? Propagate! Or what if you really love pesto and the idea of having "too much basil" isn't even in your vernacular? Propagate!

 

Propagating tip cuttings requires a bit of care, but it is an incredibly easy process if you keep its basic needs of light, heat, and hydration in mind. If I know I will attempt propagating softwood cuttings, I will let my little plants grow a few more nodes. My sweet spot is when the cuttings have at least 2-3 nodes, and the plant has 3-4 nodes remaining. You have to be careful not to let the stems mature too much because as herbaceous plants grow, their stems become hollow and hollow stems don't root.

 

Pinch plants in the morning after the dew has dried and before the heat of the day has set in to have the best material for propagation. As I said, each tip cutting should have one or two nodes where leaves grow out of the stem. Remove the lowest leaves, and place your cuttings into a hydrated propagation medium (seed starting mixes work well) so that the lowest node is below the soil surface. Most tip cuttings root relatively quickly and have little need for rooting hormone, but now would be the time if you want to use it. Look for a product designed for softwood cuttings.

 

Now let's give your cuttings the best chance for success. Place them in bright indirect light. A sunny window or under grow lights work well indoors. Outside, I would look for a shady spot. The intensity of direct sun rays can quickly burn and kill every cutting in an afternoon. I speak from experience. It's pretty devastating to lose a tray of cuttings because you left them on the front porch. Whoops! Keep them warm. Most plants don't initiate root growth until the soil is above 60F. The ideal temperature is more like 70-75F. And the last part is hydration. Cuttings lack of roots means they don't need a lot of water, but they also can't dry out. The medium should be damp, not wet, and the air around the plant should be very humid. Instead of watering the soil, you will be "watering" the leaves with humidity or mist. I personally toss a plastic dome, bag, container...pretty much whatever I have on hand to cover my propagation trays. Still, there are also misting systems that make humidity a completely hands-off situation.

 

And then we wait...

 

Softwood cuttings root rather quickly. On average, I would say anywhere from 2-4 weeks. Once you see new growth, remove the cover and do a happy dance. New growth is a sign that your cutting is on its way to rooting!!! A gentle tug on the baby plant will verify if it has rooted. Don't yank on it, but if you pull gently and it doesn't budge, it is anchored in the pot. If you feel mobility in the baby plant, put the cover back on and check again in a few days. Resist the urge to check daily. Too much yanking and prodding will damage tender young root hairs and possibly kill your chances. That would be a very sad thing. Patience is key. Once you have successful rooting, grow your cuttings like any other seedlings. Begin fertilizing weekly at half strength, and when the roots have reached the bottom of the container, harden them off and enjoy in your landscape.