Do you have a clematis that is under the weather? Possibly it had a bout with stem rot (aka wilt). Or it is just not performing the way it did last year?
Wouldn’t it be wonderful to be able to give your babies a little booster shot? No, I am not talking about some magic tonic or hocus pocus, I am talking about giving them a dose of seaweed extract. Any of you that have asked or contacted me about your ailing clematis know that I am a big proponent of this product derived from oceanic vegetation. I should start by telling you this is by no means a substitute for a regular fertilization regime. It is more like taking a supplement with your multi-vitamin tablet.
What is Seaweed Extract?
Seaweed extract is usually a derivative of Norwegian Kelp. This means it is organic. I recommend using it instead of “kelp meal” (a powdered form) even though both are derived from kelp? The basic difference between the two is that seaweed extract is in a concentrated liquid form and is water soluble while kelp meal is a dry powder. I do not think that there is anything wrong with using kelp meal on a regular basis but I believe it is more prudent to use the liquid form for an ailing clematis because it is more easily absorbed by the plant than its powdered relative. It can be applied as a drench, but even better, although (admittedly) more time consuming, is to spray a diluted solution directly onto the leaves. It is well worth the extra effort because the mist penetrates into the leaves pores (stomata’s). This means the ailing clematis does not have to wait for the root system to distribute the extract, thus it is able to absorb it more quickly and be on the road to recovery that much sooner.
What Does Seaweed Extract Do?
Giving a plant a dose of seaweed extract helps accelerate the production of a healthier root system while at the same time conditioning the soil, which helps the plant to become more disease resistant. How does it promote a stronger plant? Seaweed extract contains plant growth materials such as auxins, cytokinins and gibberlins as well micronutrients such as zinc, manganese, magnesium, iron, trace elements and vitamins, which all contributes to a stronger and healthier clematis. Since it aids in promoting a stronger root system, I also use it every time I plant a new clematis or transplant an old one. I do not just treat my clematis to this kelp cocktail, but the rest of the plants in my garden as well.
Seaweed Extract and Stem Rot
Just to set the record straight, there are no known cures for stem rot at this time. Whether stem rot is caused by a fungal disease or a type of vascular problem, the end results are the same: a “weakened” plant.
So, if your clematis succumbs to “wilt” (aka stem rot) this is the perfect time to give your clematis a prescribed amount of seaweed extract because your plant is under a lot of “stress”. Your clematis needs to use all its strength in resisting this fungal attack and/or recovering from slow circulation. Giving it a dose of seaweed extract is just what the doctor ordered. This is the only time that I recommend not feeding your clematis because it encourages foliar growth which prevents the plant from utilizing its resting process which is essential for its recovery. Start feeding your plant again when it starts putting on new, healthy growth on its own (usually after a month).
FYI: I read an article that said adding extract to your insecticides will make it more effective while another stated if it is used in conjunction with fatty acid pesticides (such insecticidal soaps) it would reduce phytoxicity (the burned tips or leaf scorch). I would like to take this idea one step further and suggest you add it to your Physan 20 when spraying a clematis that has had wilt. This way you will be doing double duty by sterilizing the remaining stems and soil around the plant while inoculating it at the same time.
The Queen’s Rx
My suggestion for you is to always have a bottle of this wonderful brown elixir in your apothecary because you never know when you might want to give your clematis “CPR” or a quick pick-me-up!
Sources: I have been using a seaweed extract that is manufactured by Grow More, a company here in Southern California, but, if you are interested, there are other brands available (hopefully) at your local nursery or you can mail-order it. You might try Maxicrop or Nitrozime.