Liquid Kelp Fertilizer
 

I got a small jug of it to aid in root development. I mixed up a gallon of it (its comes very concentrated) and I was just wondering how long the extra that I have is good for once its been mixed with water? I only used about a quart of it so I have quite a bit left. I don't want to throw it away but I also don't want to risk hurting the orchids if it is growing bacteria or something. I looked all over the bottle but it doesn't say anything about how long its lasts. Any ideas?

I've never read anything about the shelf life of those products once they're mixed. Using it in a week or two probably won't hurt anything but it may lose some potency. For a couple of years I would mix a gallon, just like you did, and then only use part of it. It finally occurred to me that the per gallon amount is just a ratio. Now I mix a half gallon or even a quart by using 1/2 or 1/4 of the amount of the product. In other words if the product calls for 1 teaspoon per gallon. I'll mix 1/4 of a teaspoon in a quart. The kelp product that I use calls for 1 ounce per gallon. An ounce is 6 teaspoons so I use one and one half teaspoons in a quart. By the way, the plastic spray bottles from Home Depot or Lowes, are approximately a quart.

Tucker, I have not used one of the kelp products.

What is your opinion, are they as effective as claimed in producing more root growth? What brand (or brands) do you use?

I use 'Maxicrop' seaweed mix and I use one capful (cap cover of the bottle) for one gallon water. Weekly but every other week in winter. The roots get robust and healthy.

Under my growing conditions in South Florida, kelp is very effective at promoting new root growth in most of my orchids. The one I use is called Maxicrop Liquid Seaweed. A couple years ago I used it every week, mixed in with my fertilizer, but I now think that was more than necessary. I now use it every two weeks. I mix one ounce per gallon with my fertilizer water but I grow outdoors in a sub-tropical climate, I think growers up North or growing indoors should probably use a lighter dose. Maybe 1/2 ounce per gallon. It's not a fertilizer so you still need to use a regular fertilizer. I think it's a good product.

I have always used MaxCorp Liquid seaweed too. When I started using it, over a year ago, I was astonished by the difference it made in my plants. (Do I sound like a cheesy commercial?) :blushing: Seriously? Why didn't I know about this stuff 25 years ago? :((

About three months ago, someone mentioned to me that all Kelp isn't equal in quality or effect so I embarked on some research of my own. I learned about a type of kelp (Ecklonia Maxima) that grows in large underwater forests off the coast of southern Africa. I read article after article...study after study...and decided to give it a try. Apparently, Ecklonia Maxima contains more auxins than cytokinins than any other type of kelp.

Auxins are chemicals, as such, that stimulate root growth, which in turn increases water and nutrient uptake. The new root tips release cytokinins which are transported up into the top of the plant and stimulates growth and the division of cells. Doesn't THAT sound exciting? :rofl: It gave me a thrill! :biggrin:

So....I searched and searched for Ecklonia Maxima and found KelpMax! I just started using it actually, so I can't report on it's effects quite yet. We shall see! :)

Thanks guys! I honestly wasn't sure how much I was going to need to spray each of my orchids so I just went ahead and mixed up a gallon. Now I know I could do 1/4th that much and have enough.

jocierk, with regard to your original question, here is some info. There are several plant hormones in seaweed extracts, and they differ quite a bit between different products. For example, KelpMax/Kelpak seems to have high amount of auxins (the hormone which promotes branching of roots). But other products like Maxicrop do seem to promote root growth in some vegetables.

Auxins break down with light. According to one experiment, if auxins are exposed to moderate light for 4 days (16hr/day, 74 micro mol/m^2/s, which is the intensity lower than what you use for Phal and Paphs), 50% of auxins are broken, and almost all gone after 10 days. If it is kept in dark, 70 and 30% or so of natural (IAA) and synthetic (IBA) auxins were lost after 30 days, respectively. Here is the abstract of this paper.

On the other hand, other hormones like Cytokinins (the main ingredient of Keiki paste) are more stable than auxins.

So keep the concentrate and working solutions in dark (and cold). It is unlikely that stored diluted solution will hurt orchids (it may not be effective, though).

Can someone tell me if kelpmax is available at lowes or home depot? Im gonna be making a trip to DFW so if there is a chance I could find it I am all for it. My old bottle of seaweed extract is almost out and i am all for trying better product.

You can buy Organicare Seaplex, cold processed seaweed, from Texas Hydroponic.
Texas*Hydroponics*&...
or any seaweed but is better Liquid Karma from Botanicare

http://www.growstorefinder.com/grow-stores-in-TX.php

KelpMax (from Ecklonia maxima) is only available via Ray (in the US).

There is a study to compare six different seaweed extracts (Stirk and van Staden 1997. J. of Applied Phycology 8: 503-508). It used Mung Beans to measure the root production. KelpMax does have the highest root production (when it was used at a really high concentration). But at the concentration we use (2 tsp/gallon = 0.26% v/v), the difference among products were relatively small. There was no statistics, but KelpMax and Maxicrop were similar at 0.2-1%, and they appeared to be better than others. But this experiment is just one side of the plant growth regulators, and other aspects could differ among products. For some reason, the authors of the study made the concluding statement that the levels of auxin- and cytokinin-activities were similar among different products.

Oh thank you! I found it on amazon, its not that much more than what I paid for my other stuff.

Seaplex is from Ascophyllum nodosum, which is the common source (e.g. Maxicrop). JFYI.

@ Naoki you just talked so far above my mental capacity haha:blushing::rofl:. Thank you for the information, I appreciate it.

But ya'll were of great help, I have new items to check out! the better the products the better the plants.

So putting it in clear glass bottles on the shelf below my Catt's under a four bulb T5, in my midwest house with a broken air conditioner, probably wasn't the best way to store it? Oh well…I'll mix a new batch this weekend.

This is the one I got: Amazon.com : Liquid Kelp Organic Seaweed Fertilizer - 32 Ounces : Patio, Lawn & Garden

It had good reviews and I didn't think about the possibility of different types of seaweed being better than others. It wasn't super pricy so no big deal if its not the best and I need to replace it.

Thanks so much for all the info. As usual, you were all super helpful! :)

Because I don’t have access at KelpMax, I used seaweed from hydroponic stores and there are a lot of “sweets” and I don’t think if in study to compare six different seaweed extracts are included a serious company.

I think that Kelpmax is only available online from First Ray's.

Yeah after I asked that my neuroreceptors kicked in and I remembered that that was from ray...college finals are dangerous on your brain!! :rofl:

I also use whichever kelp I can find because it is not really accessible where I live. But so far it seems either of several brands I have used really do have a positive effect on root growth. I always use it when I get a new bare root plant or have one that is struggling. I never had the kind of root growth a couple years ago that I now have.

One of the containers said it does not store well once mixed and I keep my liquid kelp in the fridge in its concentrated form. I only mix enough to use at one time except if I soak roots on an ailing plant I will keep the solution in a cool dark place or fridge and soak them again in a week after I have brought it to room temperature.

One of the nice things about KelpMax is that, unlike most other brands, they have found a combination of organic preservatives to add to it, giving it a room temp stability of "at least two years" according to the producer.

The samples I got from the US distributor was 30 months from manufacturing, and that is what gave me this, a couple of weeks after a single application:

http://www.firstrays.com/Pictures/Ke..._branching.jpg

A picture is worth a thousand words!

Just for anyone reading this in the UK.

I have had great results from 'Shropshire seaweed' which is available either on Amazon or on their own website.

I've kept that for 12 months and found it still effective (no idea how long from manufacture it was). I got massive flushes of roots from orchids that had struggled for years hardly growing any roots.