I don't purchase anything that is specifically labeled root stimulator. In most fertilizers, there are three numbers listed. The first is nitrogen which stimulates green growth, the second is phosphorus which stimulates root development and flowering, and the last is potash which has various functions including giving winter hardiness to plants. If you purchase a fertilizer with a high middle number, you will in essence be using a root stimulator since phosphorus does stimulate root growth and flower production. Another option would be triple phosphate but since it is just phosphate, I prefer using a regular fertilizer with high phosphorus so that I get all three in one versus just applying something called root stimulator.

I personally don't think that adding something marketed specifically as a root stimulator is good for anyone but the person selling it and their pocketbook. I don't also don't think that it is going to speed up the root development of the plant any better than a good compost application, a good fertilizer that has sufficient amounts of the 3 components, or using alfalfa pellets which contains a hormone that helps plants produce more basal shoots.

I'm right behind Miguel on this one! There's a lot of anecdotal reports and "testimonials" out there about the value of root stimulators, but there is no scientific evidence that supports they provide ANY benefit to plant roots. Many include vitamin B1, sometimes auxins (plant growth hormones) and usually some sort of basic plant nutrients (NPK).

Plants manufacture their own B1 and it is also supplied by the organisms that reside in healthy soils. And there is nothing to substantiate that B1 achieves any faster root growth than the plant will manage on its own. Most claims regarding the efficacy of B1 come from the tissue culture industry however those sets of growing conditions do not come anywhere close to the issues involved with home gardeners and inground planting of fully developed plants.

Growth hormones are expensive and generally unnecessary. These are the same products used in rooting compounds for propagation purposes with cuttings. They may be fine and even advised when you have no roots to work with but won't necessarily have any measurable effect on a plant with an already well-defined root system. And in some cases, these will inhibit top growth to some extent, which is not exactly a desirable side effect.

The nutrients they contain may be of value, but as Miguel notes, you will achieve similar results by just using a complete fertilizer rather than something that is packaged as a "root stimulator". Personally, I never fertilize newly planted material (aside from providing a slow release product to container plantings) but just rely on good soil and a well-prepared planting hole followed by an organic mulch to start things off. And water - plain old water is generally all the stimulation ever needed to get roots growing.

Establishment of a plant in the landscape is a process that just takes time. You can't rush it or speed it up - it is what it is. Planting the vine deeply and pruning back the clematis hard for the first couple of seasons (appropriate for any pruning group) will encourage the formation of a strong, healthy root system as well as increasing the number of basal shoots (eventual stems) that arise from the root crown.

And I am behind his last paragraph 100%. The only ones benefitting from so-called root stimulators are those who market and sell these products - not the plants and not the gardener.

I agree with Miquel and gardengal, the only thing I use is compost and alfalfa meal along with a little timed released fertilizer in the spring. Inexpensive, it improves the soil, and provides the plant with all that it needs to establish roots, grow and bloom.

Carol

Thank you for the tips. I will have to look into the alfalfa. Do you purchase the alfalfa at a nursery or a home and garden center? I can't recall seeing it but then I have never been actively seeking it out either.

Carey

I purchase alfalfa pellets at a local farmers feed and seed store. It is a food used for horses and rabbits. Although some have said that it contains salt and may harm the plants, I have never seen any adverse affects of using it on clematis or the grass.

Miguel, in the UK they are selling a product called 'Root Grow,'which is some sort of Mycorrhizal fungi that is supposed to be beneficial to plants.
Here is the Canadian version, I thought it was worth trying, what do you think?

Well I can't post the url, the server says it is spam and I am trying to sell a product.
Do you know anything about Mycorrhizal fungi, and is this the sort of product Carey was enquiring about?

Helen, don't have a clue what specific product Carey was talking about since she didn't give specific information--just general info of a product called root stimulator.

I believe Peer on GB has talked about using some sort of mycorrhizal fungi but I think this is something relatively new and know nothing about it. I would like to see some independent data on it to see what it is all about. I would be leary of any info coming from someone selling it since I could hardly expect their opinions to be unbiased. Will have to see if I can do some research on it.

If you have already purchased it Helen, why not go ahead and give it a go. It would be neat if you could do some tests on two similar plants that are of similar size and treated similary except one treated with the fungi and the other not to see if you can see any demonstrable results.

I went out into the garage and brought in my dirty bottle of root stimulator to check it out some more. It is labelled as Green Light Root Stimulator & Starter Solution 5-15-5. So, I'm guessing this is just a weak fertilizer aimed at root development and flowering and lesser green growth. It doesn't list anything about mycorrhizal fungi.

Thanks again for all the helpful information.
Carey

Thanks for the Mycorrhiza 101 tutorial gardengal. Hadn't gotten around to investigating it today since my original post in response to Helen's post was made way early this morning before going in to work. What specific brand of potting soil and compost contains this mycorrhizal innoculation?

Thanks, Miguel. On rereading it, it comes across a bit "school teacherish", which was not my intent :-) The relationships these organisms create really is a fascinating subject......or at least I think so. Maybe that's saying something indirectly about my social life - who knows!!

The soil products are marketed under the brand name of Gardner & Bloome. AFAIK, they are exclusive to the west coast.

Pam - gardengal

I used a product called BioVam with my newly planted clematis and roses this past year. BioVam is essentially the mycorrhiza fungi. I am trying to get a good symbiotic relationship going a bit more quickly.

Robert

Perhaps it is my scientific nature Pam, but the info didn't come across as school teacherish to me. Very informative and something that at one time I had meant to look into and never got around to it. I would guess that making sure you add a lot of organic matter to the top of the soil around the plant (I do that vs. adding it to the planting hole since I garden in clay and don't want the swimming pool effect) or to the potting mixture you grow the plants in would do wonders towards establishing the type of mycorrhizal population that you want, although it would be slower to reaching the roots than adding something in with the planting soil.

I figured the compost and potting material would only be a locally available commodity.

Robert, it would be interesting to see if you planted some plants with the BioVam and some without, if you could see any real difference between the two groups. Of course if you are comparing different rose or clematis varieties, it might be difficult to tell which were positively affected since different plants would probably react differently with or without the additive.

Miguel, haven't purchased any as yet, the shipping costs as much as the product, maybe I can get the local hydroponic shop in Moncton to get it in, or better yet, they just might have some in stock.
Will find out soon.

Pam, thanks for the information, didn't find it schoolmarmish either, very comprehensive.

Helen, I looked around for some of it on the web and found it to be quite pricey as well. I thought it might be interesting to try some of this stuff mixed with vermiculite that we start our clematis seed in to see if it helps with the rooting process. If I do find some I may trial it on some seedlings I have already that are of the same type when I pot them up. This is of course contingent on finding some that is reasonably priced.

Miguel, the stuff I found was 18$ Can for one pound and it says to use 1tspn per gallon of grow media.
I wonder how many tspns you'd get from a pound of this stuff.

Three years ago we had a burr oak planted in our yard.This is a very slow growing tree. The nursery told me if we would use MYKE in the planting hole, the tree would be guaranteed for 5 years for anything. The little box of stuff was $13. The first year this tree grew exactly 1 foot. Normal growth on this tree is about 2 inches a year. The tree is now in the ground here 3 years. Growth for the last 2 years is about7 inches. This spring I'm going to use it when I plant clematis, just to see what will happen.

Never heard of Myke and tried googling it and came up with the following link below. It appears it is a mycorrhizial product of the sort we have been talking about. I personally believe if you amend your planting hole with compost or even topdress with it, you are going to be adding the necessary nutrients and microorganisms so that the plant should be able to form the relationship between the naturally occurring fungi and its roots so that adding any external source of mycorrhizal fungi is unnecessary. To me it is like purchasing a compost activator when all you really need to do is make sure you have the proper nitrogen to carbon ratio in your compost mixture. I do think however for those plants or seedlings planted in soilless mix it might be interesting to try to see if it helps them since the fungi and other components in soil wouldn't be present in a soilless potting mix or seed starting mix.

Here is a link that might be useful: MYKE

Just a note here to tell you about the soil I have. There is about a foot of topsoil and then I have gyp. I could make bricks out of it. I've gardened here 42 years, using compost, manure peat, and lots of alfalfa, the latter mostly for mulch. Consequently when something comes along that makes my life easier, I use it.They tell us when planting trees not to amend the soil much or the roots will not reach out and tend to stay where the good soil is. I have found out here clematis will do the same, In fact I drowned 2 clems. they were living in a sump hole. Next spring I'm going to try a couple of clems with nothing but the MYKE.

Sounds like the soil we have here in the south except my nemesis is clay. Digging holes and over amending it with much of anything will result in swimming pools that plants will rot in when we do have rain. What I have found is that adding a little additives to the hole, compost or composted pine bark chips, to help with moisture percolation and spreading mulch and organic matter on top of the soil will eventually generate a tilth to the soil in the manner that Mother Nature generates it naturally. The amendments will decompose, attract worms that will till the material deeper into the soil, and will deposit their own natural droppings to the soil which will increase tilth. Another little known thing that adds organic matter to the soil is the natural death and decomposition of root hairs on roots. I suggest you read a good book on permaculture to learn about how people can generate growing conditions and grow plants in less than hospitable conditions. A good one that was a real eye opener to me was a book entitled "Gaia's Garden--A Guide to Home-Scale Permaculture" by Toby Hemenway. I wish I had read it years ago when I first started gardening.

No one, myself included, is telling you not to use something that makes your life easier, but as is often the case, there is often more than one way to skin a cat and permaculture techniques are a means of accomplishing this which do not involve something that is purchased in a container and are much less expensive in the long run and better for the environment.

I just thought I would chuck my two cents in here. I find that a couple of shovelfuls of well decomposed compost including aged manure and a generous handful of bone meal mixed into the native soil achieves a healthy root system and doesnt cost much at all. I use this mix with everything I plant, annuals, roses and my soon to be much larger collection of clematis and my vegetable garden. The beds that did not get the bonemeal last year (I ran out and didnt bother to go get more) produced OK but did not develop as strongly. Admitedly, these were veggie beds and the sunflowers, all heavy feeders to begin with. Anyway, just plug for plain old bonemeal. Kat