Why would you?

Root hormone stimulates rooting, it doesn't (unless it has fungicide in it or antibiotics) act as a panacea to fungal or bacterial root rot.

It would probably burn existing roots unless very weakly applied (and what's the point of that). Opinions differ if it actually even helps rooting or sometimes even impedes it.

Edit: I haven't used it to root things in over ten years, and I actually think I get better success without it. I almost never fail to root any cuttings taken (and I take a lot).

Al

A product called Superthrive was pushed here by a corporate re on this forun. Are you familure with it. Could you share your thoughs on this product. It toted healthier roots when used.

Steve

I wrote something many years ago about what I've personally observed what Superthrive does or doesn't do. It was published in an online magazine called (I think) Stemma (Stella?) Anyway, it was for Hoya aficionados.

Superthrive or Superjive

The question regarding the value of Superthrive as a miracle tonic for plants is often bandied about in horticultural circles. Over the years, I had read claims that ranged from, “I put it on my plant, which had never bloomed, and it was in full bloom the next day.” to, “It was dead - I put Superthrive on it and the next day it was alive and beautiful, growing better than it ever had before.” I decided to find out for myself.

If you look for information on the net, you will probably only find the manufacturer’s claims and anecdotal observations, both so in want of anything that resembles a control. Though my experiments were far from purely scientific, I tried to keep some loose controls in place so that I could make a fair judgment of its value, based my own observations. Here is what I did, what I found, and the conclusions I made about any value the product Superthrive might hold for me.

On four separate occasions, I took multiple cuttings of plants in four different genera. In each case the group of cuttings were taken from the same individual plant to reduce genetic variance. The plant materials I used were: Ficus benjamina, (a tropical weeping fig) Luna apiculata (Peruvian myrtle), Chaenorrhinum minus (a dwarf snapdragon), and an unknown variety of Coleus. In each instance, I prepared cuttings from the same plant and inserted them in a very fast, sterile soil. The containers containing half of the cuttings were immersed/soaked in a Superthrive solution of approximately 1/2 tsp per gallon of water to the upper soil line. The other half of the cuttings were watered in with water only. In subsequent waterings, I would water the “Superthrive batch” of cuttings with a solution of 10 drops per gallon and the others with only water. The same fertilizer regimen was followed on both groups of cuttings. In all four instances, the cuttings that I used Superthrive on rooted and showed new growth first. For this reason, it follows that they would naturally exhibit better development, though I could see no difference in overall vitality, once rooted. I can also say that a slightly higher percentage of cuttings rooted that were treated with the Superthrive treatment at the outset. I suspect that is directly related to the effects of the auxin in Superthrive hastening initiation of root primordia before potential vascular connections were destroyed by rot causing organisms.

In particular, something I looked for because of my affinity for a compact form in plants was branch (stem) extension. (The writer is a bonsai practitioner.) Though the cuttings treated with Superthrive rooted sooner, they exhibited the same amount of branch extension. In other words, internode length was approximately equal and no difference in leaf size was noted.

As a second part to each of my “experiments”, I divided the group of cuttings that had not been treated with Superthrive into two groups. One of the groups remained on the water/fertilizer only program, while the other group was treated to an additional 10 drops of Superthrive in each gallon of fertilizer solution. Again, the fertilizer regimen was the same for both groups. By summer’s end, I could detect no difference in bio-mass or vitality between the two groups of plants.

Since I replicated the above experiment in four different trials, using four different plant materials, I am quite comfortable in drawing some conclusions as they apply to me and my growing habits or abilities. First, and based on my observations, I have concluded that Superthrive does hold value for me as a rooting aid, or stimulant if you prefer. I regularly soak the soil, usually overnight, of my newly root-pruned and often bare-rooted repots in a solution of 1/2 tsp Superthrive per gallon of water. Second, and also based on my observations, I no longer bother with its use at any time other than at repotting. No evidence was accumulated through the 4 trials to convince me that Superthrive was of any value as a “tonic” for plants with roots that were beyond the initiation or recovery stage.

Interestingly, the first ingredient listed as being beneficial to plants on the Superthrive label is vitamin B-1 (or thiamine). Growing plants are able to synthesize their own vitamin B-1 as do many of the fungi and bacteria having relationships with plant roots, so it's extremely doubtful that vitamin B-1 could be deficient in soils or that a growing plant could exhibit a vitamin B-1 deficiency.

Some will note that I used more of the product than suggested on the container. I wanted to see if any unwanted effects surfaced as well as trying to be sure there was ample opportunity for clear delineation between the groups. I suspect that if a more dilute solution was used, the difference between groups would have been even less clear.

It might be worth noting that since the product contains the growth regulator (hormone) auxin, its overuse can cause defoliation, at least in dicots. The broad-leaf weed killer Weed-B-Gone and the infamous “Agent Orange“, a defoliant that saw widespread use in Viet Nam, are little more than synthetic auxin.

Al

Al Thank you.

This was important to me. I finished a full time job protecting my demented parents from fraud and stealing. It was very hard. I personally would never fall for these kind of scams but I have friends her and elsewhere that are taken again and again .. You are probably the most respected and hear person on th garden web and your answer will carry a lot of weight should this superthrive or other hoaxes come by us again. My wife and I are getting older to. Despite our being mentally unaffected by age we are bombarded daily for items and services with outlandish clams and costs. It gets worse as we age. I am very irritated after fighting off these badgerers over the past few days.

Steve

Thanks for the very kind words, Steve. I'm not getting any younger either. I was supposed to retire in Jan '18, but my brother was discovered to be terminally ill, so I've been working like mad since last Oct to pick up the slack created by his absence. Lawyers are working on a complete stock and assets transfer to a new holding company/owner now, and are on the home stretch. Looking to be retired inside of a month. I hope nothing happens to mess up the deal.

My mental acuity is still fairly intact, but it bugs me that my short-term memory sure ain't what it used to be. Thanks again ...... and good luck!

Al

Al, I second what Steve said! Also so sorry about your brother. By the way, my short term memory was shot long before yours, even when I met you at the age of 30. Don't feel bad and thank you for keeping in touch here. You are a rich blessing as always.

Good luck in your retirement. Just think of all the time you will be able to spend with your passions. Good for you)