I don't think he's knocking it at all. The last line in the post sums it up. People pay for convenience. There is nothing wrong with that. You can make you own with a lot of studying and education and work as xtsho say's, or you can buy it conveniently and correctly pre-made. It's up to you. Personally I go for the convenience of the pre-made stuff like that myself. My grows are small so the premade stuff lasts me several years, so it's not a big expense in my opinion. If you are commercial grower with hundreds or thousands of plants you probably wouldn't want to spend the money, but for a few plants a grow it's not a waste, imo.
I'm not knocking the science behind adjusting the levels of the nutrients to give plants based on their growth stage. I'm just able to replicate the same thing that these additives do without the need to purchase overpriced products. I buy the same things in those fancy bottles only hundreds if not thousands of times cheaper and add water myself. I can replicate most any additive.
I have 95% fulvic acid, kelp, epsom salts, monopotassium phosphate, calcium nitrate, micro nutrients, etc...I have things I bought to make my own version of an additive that I don't use because I never saw any benefit from using it. I'm open to adding additional elements into my nutrient solution.
Today I decided to give silica another try just for the heck of it. I'm doing my own modified mainlining technique on a few plants and have read that silica can help increase the strength of branches and stems. Because I am anticipating eight large cola's I'm concerned about the strength of the plant. Silica might help so I'm adding 15 ppm of potassium silicate to my nutrient solution to be added for the next two to three weeks of the vegetation stage.. I bought a pound of potassium silicate for less than $20. I can make over 100 gallons of those $20 one liter bottles of silica additive that all the big nutrient company's sell.
I understand that most people don't want to take the time to learn about plant science, nutrients, etc... I do it as a hobby. I grow and cross various vegetables and flowers as well as cannabis. I like growing things. I use the same technique I use to grow cannabis for vegetables and vice versa. This year I grew the biggest tomato in my entire life. 21.5 oz's. Sure they are people growing bigger but next year I'll grow a 40 oz tomato.
The thing that bothers me the most about nutrient companies is that they have people convinced that they need their snake oil products. I understand people that know what they're doing and just want the convenience and are not concerned with the cost. The marketing they use and the amount of people that are convinced that if they just buy twenty bottles of their products pounds of killer bud will magically appear on their plants. Those people end up in the marijuana problems section.
One word of advice to everyone is it's better to start with half strength nutrients and increase if your plants need need it. Overfeeding causes the majority of problems people have. And the worst thing is that many end up adding other components to fix a deficiency caused by a nutrient lockout due to over feeding. Sometimes the grow medium gets to the point that the various elements start reacting with one another and form other compounds that the plant can't use causing the deficiencies people people have because a certain element mixed with something else has been turned into chalk making it unavailable to the plant.
I have no formal training and don't claim to be an expert. All I have is my own experience. You'll have to decide if I'm credible.
