Willow water is very old and very well known method of rooting plant cuttings.
Willow or Salix species naturally contain a mix of both Indolebutyric acid (IBA) and Salicylic acid (SA) and it’s effectiveness for assisting rooting plants is undeniable.
There is also a multi-million dollar market for commercially produced powder or gel products, and these proliferate the garden market. Indolebutyric acid (IBA) is the only “active ingredient” or “active constituent” in any of these commercial products. Active ingredients and Active constituents are the bit shown to the job. They are the only thing doing any of the job you paid them for, which is creating well-rooted healthy plants.
The rest of their recipe is colours, fillers like talc and chalk powder, gelling agents like agar and gelatin, and preservatives to stop the chemicals from breaking down over time, or splitting into layers like 1-Naphty-Acetic Acid and in every case, they make up more than 90% of the product.
Few random examples:
- Rootex ACTIVE CONSTITUENT: 8g/L INDOLE-3-BUTYRIC ACID
- ROOTEX-L ‘Hormone Root Liquid’.Active constituent: 4g/L Indole Butyric Acid
- ROOTEX-P ‘Plant Rooting (Cutting) Powder’ 3g/Kg Indole Butyric Acid
- Clonex Green active ingredient 1.5 g/L IBA for herbaceous and softwood cuttings
- Clonex Purple active ingredient 3.0 g/L IBA for semi-hardwood cuttings
- Clonex Red active ingredient 8 g/L IBA for hardwood cuttings
IBA is the only bit that matters in all their different recipes, as its the only active ingredient.
So if you can create a product with a decent mount of IBA yourself at home, then you have something just as effective as anything else on the market
If you do it yourself at home it’s nearly free! Even cooler than that the stuff I make just works better at establishing healthy strong new plants and if you keep reading I will explain why.
Salicylic acid (SA) is not present in the other commercial formulations as it is very volatile and a bit expensive.
It is hard to store inert, it’s quite reactive, and as an acid, it breaks down all the other chemicals in the gels meaning they can not be stored as long. The thing is, it really is a good thing to have as it is a plant hormone that signals damaged plant tissue to defend an attack from pathogens like bacteria and fungi.
It triggers the immune system via SAR (systemic acquired resistance) whereby an attack on one part of the plant induces a resistance response to pathogens, in other parts of the plant. It’s an alarm that triggers the plant’s internal defences.
Even more amazing it can also trigger a defensive response in nearby plants!
It does this by converting the salicylic acid into a volatile chemical form that is taken up via the surrounding air and detected in nearby plants. Completely separate plants that are no in any way physically connected to each other, know there is danger around and toughen up ready for an attack. Super cool hey!
Unfortunately, the individual plants that are attacked first often do not produce enough Salicylic Acid to defend themselves effectively. So those guys die, but they tell their mates on the way out which is very valiant of them.
But if your rooting hormone mix is made from both IBA and SA, you have effective root production AND increased immune response meaning less damping off or disease dramas later on. Application of both IBA and SA just works better than IBA alone and there is a heap of scientific studies to back that claim.
Oh yeah, on a final note, SA it is not quite the same as an “Asprin tablet”, but it is very similar. It is the bit left over when aspirin pills or powders break down and start to decompose and oxidise. So adding an aspirin pill could have a positive effect to a cutting powder or gel, or it could be a good thing to spray on plants just as the wetseason flooding starts, or before the big dry, maybe, but crushing the pill and leaving it exposed to the air for several weeks then adding it to a commercial product is probably better.
The only problem with that is it will also immediately start breaking down the IBA which is worse…
When you make Willow water, both salicylic acid and IBA are extracted from the willow tissue and concentrated in the resulting tea, and stress is a major trigger for production. Willow species naturally have heaps and are a common weed that is pretty much everywhere people are here in Australia.
Willow water Recipe.
- Find a willow tree. Any Salix species will do the job, but the twisted ones are not as good as the straight stemmed species.
- Bend the last metre of a nice thick branch roughly, in a mean and aggressive manner, bruising the bark with your hands, stretching but not breaking the internal fibres.
- Leave it for 4hrs. This gives the plant time to send a rush of hormones and auxins to the affected area and in studies done by chemist/botanist mates overseas, they saw massive increases of both IBA and SA when this was done before harvest. A longer time wasn’t any better, less time was less effective. ~4hrs was spot on.
- Cut off the 1metre of stressed branch quickly and cleanly with a saw or snips, and immediately put it in a bucket with 1lt of water, cut end down so it can soak up water. It will then begin to draw in this water and swell, and the bark will begin to loosen a little.
- The next day peel and remove all the now loosened bark and leaves and then blend the plant to sludge in a food processor or similar device. Throw the remaining smooth inner wood away or use it as a tomato stake.
- The resulting slightly thick cloudy “tea” is then boiled for 10minutes in a large pot with no lid. It is then removed from the heat and left to cool.
- Once cool very finely strain it, squeezing the pulp as much as possible to get all the liquid and goodies out. That original 1litre of water gets you about ~800ml rooting hormone. That is a hell of a lot of cuttings!!!
It has a very high concentration of Indolebutyric acid (IBA) and Salicylic acid (SA) which are both useful in helping plants throw roots and in my trials, it works at least as good if not better than the fancy commercial stuff.
Plus it’s kinda free…
The only downside is it does not store well at room temperature soon fermenting. To avoid this it’s best to just freeze it in small ready to use portions and to do that I just use an ice cube tray.
I then defrost a single cube in a shot glass as it’s needed.
It can also be boiled into agar instead of the water component when making gels and tissue culture mediums and I talk about that in greater depth at the Bodgy DIY tissue culture page.
Willow water is awesome stuff and I highly recommend it!
If you want to get even fancier then my 55 site Acrylic Aeroponic Cutting Cloner design is worth a look too.