AusBonsai

I have been a big fan of seaweed extracts for a long time in my veggie patch and have been using it with my bonsai after repotting and after pruning, as well as using powerfeed every 2 weeks. I am currently studying Landscaping at Tafe, which includes several horticulture subjects. Recently the topic of using Seasol as a ongoing fertiliser was brought up. My teacher/lecturer explained seasol was virtually useless as a regular fertiliser, instead only really being good for transplant shock or after times of stress. He argued that the main benefit of seasol was to increase microbial activity in the soil and add trace elements. I know alot of people use this product religiously and was wondering if anyone else has heard this? Believe this? Whats everyone opinion on the matter?

The below is a cut and past from Seasol's FAQ:

Seasol is made from pure Bull Kelp. It is not, by definition, a fertiliser (as it contains only marginal nitrogen and phosphorus levels), however it is a dynamic stimulant which improves the root system and increases the reproductive capacity, thereby increasing the number of flowers per plant as well as the flowering season.

So it still serves the purpose to be used religiously

I have a large drum of seasol and one of powerfeed as well.
Seasol at transplant time and two weeks later, powerfeed twice monthly after that as well as occasional osmacote, dynamic lifter and homemade fertilizer cakes.

Sounds like your teacher knows his stuff Leamos as not many horticulturists understand the uses of seasol and he has pretty much hit the nail on the head.
But there are varying opinions on how valuable regular use is. Recent research I have heard of (being done by seaweed concentrate manufacturers in USA) is that a little often (every two weeks) is the most beneficial. How beneficial is the big question.
One important thing to remember is use it strong for transplant shock and weak for regular use. Reading the label on seasol will add more info to this.

Hi leamos,
Your lecturer is absolutely correct. I always use Seasol after repotting, after seeds start to shoot and as a tonic for any plants showing stress. I alternate between PowerFeed and Charlie Carp as my liquid fertilizers. There are other fertilizer I use for long term fertilizing when repotting and general fertilizing.

Regards Ray