It’s brilliant having fresh herbs when you are cooking (or making a wee cocktail), so obviously we want to make that brilliantness last as long as possible 🙂 That’s where some clever “pruning” and some propagation come in.
Whether you’re growing herbs along with me or you have bought some plants from your local shop and followed my advice on keeping them healthy, at some point you will be faced with leggy – tall, spindly – basil plants with hardly any leaves. So shall we chat about how you can still have your basil (and eat it) and encourage the plant to grow thicker, bushier and keep providing leaves?
Basil is a very simple plant, in terms of how it grows. It’s generally one stem, with pairs of leaves at intervals. Untouched, the plant will keep putting out two leaves at a time, each getting progressively smaller creating a tall spike-like plant, which will flower on the very end of the spike.
Now how it grows is that the area on the stem which has the pair of leaves growing is where the hormones associated with growth are in the most abundance. The plant puts out leaves then grows a bit taller, puts out more leaves etc etc. However, if you pinch the plant just above a set of these leaves, those hormones then kick into action and instead of making the plant stem grow a little taller, it creates a new shoot on each side, between the stem and the leaf. So instead of one tall basil plant, you get a bushier plant with multiple stems each growing more leaves.
So how does this work in real life?
Well, what usually happens when we want some basil to use in our lovely pasta sauce or tasty pizza is that we pull leaves off the plant individually, usually the really lovely, vibrant ones that get our attention.
This doesn’t stimulate the hormones in the plant stem, so the plant doesn’t replace them and continues to grow taller, leaving bare patches where you have taken leaves. Making for tall, leggy plants.
So instead of pulling leaves off the stem like this, if we pinch from above a set of leaves, this will give the plant that little jolt, telling it to create two new stems to replace the leaves you have just taken.
Over time, creating a bushier, fuller plant. More leaves for us to cook with, hurrah.
There is one downside to this of course, it takes time for that plant to grow those new stems and create those new leaves. So if you only have the one plant, it can be a few weeks before you can use it again. But… knowing how the hormones invigorate growth is where you can take control and create new plants, for free.
We’ve already said that pinching the plant above the two leaves causes the plant to create new shoots… so what if we pinch below the leaves? Yup you’ve guessed it, we can then use the boost in growth hormons to create roots on that stem and a whole new plant.
Propagating basil cuttings
So as I just said, if we take a cutting of the plant from just below two leaves, we can encourage the plant to grow roots at this point and create a whole new plant. We do this by, taking the cutting, and removing all the leaves from the stem, except for between 2 – 4 on the very top and then popping this cutting into a glass of water.
The reason we take almost all of the leaves off is because at this point, there are no roots, so this little cutting will struggle to cope with the usual amount of photosynthesis. Reducing the amount of leaves takes the strain off the cutting, allowing it to focus on making roots. Also, as I’ve mentioned before, the leaves on the basil plant rot very easily, so putting them into water isn’t a great idea.
So you have your cutting, you’ve taken most of the leaves off and you’ve popped it into a glass of water. In a week or two you should see lots of new roots.
Hurrah, you have a new basil plant to pot up into some lovely potting compost. Imagine how many free new plants you can now make…
Got a glut of basil? Make pesto