What better way to skim over the scientific method than by talking about Salvia Divinorum!
Bman_666, over at SalviaSource, had the very noble idea of applying a little science to growing salvia divinorum in order to dispel any myths or misconceptions about it, and maybe produce the ultimate “How To Grow Salvia” guide for salvia cultivators around the world.
Some of the variables under scrutiny are:
- Natural vs artificial light
- Different soil compositions / Fertilizer mixtures
- Effectiveness of CO2 supplements
- Contained growing (with controlled humidity) vs growing out in the open
- Will your TV kill your plant? [What?! — I suppose most scientific breakthroughs develop from “outside-the-box” thinking, so I’ll reserve judgement…]
- Hydroponics vs Soil
- Watering frequency
- Misting the leaves vs not
- Varying soil pH
- Distilled/bottled/tap water comparisons
Noble goals indeed, but at the time of writing, Bman_666 wasn’t quite sure what he’d be letting himself in for! The first page of the thread in question contained some excellent insight about how the results might be structured within the forum, and some quick guidelines on standardisation, which are both important to prevent confusion and help mine accurate data. But there was one thing missing — repetition, they key to any scientific study.
Perhaps they’re way ahead of me, I thought — we could all take repetition for granted. Just to be extra vigilant (the, uhh, second key to any scientific study? It must some kind of many-keyed combination lock, with iris scanners ‘n’ all. A complicated beast!), I posted my advice on using 8 – 10 plants per variable to test. So, 4 – 5 plants for the control and another 4 – 5 differing in a single respect (ie, watered with deionised water). It turns out they weren’t as far ahead as I thought.
At this point, I’ll just point out I had to explain the same thing to someone in the lab today. We were setting up cell cultures in order to add varying concentrations of a drug (retinoic acid) to them to see what happens. For each concentration of the drug (dissolved in a solvent), we had a total of 8 cell cultures set up — 4 to receive the drug/solvent and 4 to receive the solvent without the drug, as a control. Since the concept of repetition seemed a less universal concept than I first realised, I figured I’d talk about it here.
So, back to this thread. My reply was the following:
Suppose your get set up with your soil cutting and your hydro cutting. If, for some unknown reason, the hydro cutting dies, all you can conclude is that hydro kills salvia plants.
Or, say in 1 week your hydro plant grows 10cm and your soil plant grows 9cm (I have no idea how fast it grows; figures are arbitrary). All you could conclude from that is that plants that grow in soil grow 90% as well as those with a hydro setup. Now, supposing you had 5 plants with each variable — the hydro plants grew this much {10,12,16,17,23} (average 15.6cm) and the soil plants grew by this much {5,7,8,8,9} (average 7.4) — as you can see this data suggests an approx 50% difference. Taking the tallest/shortest combinations of your 5 plants, you could end up with a height difference of as much as 18cm or as little as 1cm — working with only 1 plant per variable can give you very inaccurate data.
In reality, the ranges will likely be much narrower, but you should get the point. Even plants grown under identical conditions will not develop 100% identically, and that variable is one that you need to take into account, like any other (eg humidity). Because you can’t control that variable, the best you can do is eliminate its effects by using multiple data and averaging. You wouldn’t trust a drug that had been tested on a single individual, would you?
I hope that can highlight just how meticulous you have to be with your research. Growing only two plants side by side is great for a fun, personal experiment, but to further the collective knowledge in a particular field, you need to apply a strict scientific method.
Bman_666’s main concern with repetition was the number of plants he had available, which is fair enough. But serious science demands a serious commitment. From an idea in the mind of a chemist, to an actual prescribable drug, pharmaceuitical companies have to spend hundreds of millions of dollars on research, involving trials of thousands of people.
While the details may be a bit out, the SalviaSource guys are certainly making tracks in the right direction. If you have 10 or so salvia clones lying around, maybe you can contribute to this fascinating project? Be sure to get involved @ SalviaSource!
i have been growing thisplant for over 24 years, and at 52 degress north lat, i find a difference then the original 16 degrees north lat i originally started growing at, i have over 112 trials spanding 12 years, and in many different erra and climes. I have even gorwn in southernhemispere, i find this plant produces diferent trengths at the same volume, at different climes, but never found the soil or other medium to be a big difference only in small details ph, etc.
themain way to get the original strength of the plant is to grow out the clones you have for 5 years, i did 12 years, then began my trials, then the last 12 years trials even ending this year prove that 16 degrees north latidue grows a stronger more potent plant rather then a 56 degree north lat plant gown in soil. again if you double the volume, you will still get the same effects. I also find the internet provides the most harsh ways of reducing the extract, using zippo lighter fluid you never need that to do the job, if you have had botany and chemistry and biology, gime a break, you would likly kill yourself cooking zippo fluid and whatever other solution they put in the days reciepe. I will advise I have only seen the plant flower twoice on two seperate plants in two seperate hemisperes in 24 years, one was white and one was violet or lilac colour in a stalk like fashion, i have a mother that is 10 years old and has produce more clones then any otherplant I am continually growing, I grow every day over 50 new plants, and harvast over 500 pounds a year of leaves, these are all from frankly different locations around the world, with different properties.
I hope you find this helpful
geheim
Hi geihem… I live in Winnipeg in Canada (50n lat) and have started growing plants. Is there a certain kind of fertilizer you recommend.