Its like learning from your grandpa,the best and most loving class out there! Amazing is an understatement! Lots of love Aditya
Rated 5 out of 5

~Aditya Jain


I'll probably watching this 10 times each just to absorb the amount of information. I do wish it was 99% lecture. The best videos are the propagating and cloning. The visual guides are easier to absorb. I'd like to see a class on identifying what the plant needs so we know how to "spoon feed". Thanks Harley!
Rated 5 out of 5

~Andy Chapman


It's also nice to finally be on board with professionals, will look into "street science" in the future, that's sweet. I want to thank you Mark for taking the time and giving the attention needed for my order even tho I'm not a big commercial facility. I've been a licensed medical grower for 3 years now since I was diagnosed with perianal abscess, 11 surgeries since 2017. That's what fueled me to reach out to someone like you. I'm precisely following the all in one feeding schedule hoping for great results! Pleasure doing business with you. Happy Growing!



I’m a medical cannabis patient that is on long term disability. For the last 3 years I’ve been dedicated trying so many different products and experiments to get the best medical cannabis I can possibly achieve, as well as answering questions that I had for myself. I have to say that your Grow & Bloom beneficial bacteria & microbes is an AMAZING product. I had soil problems in the past such as pyth and once I starting using this product I’ve never had a problem again. But it doesn’t stop there. I did a few side by side comparisons and noticed a big difference. The side with the microbes was more vigorous and looked that much better than the side without. The final result was amazing too. The side with the microbes tasted so much better and was more potent than the side without. Every grower using soil/soiless should be using this product

~Patrick H


I've been growing for over a decade using different brands of liquid fertilizer and their feeding charts but never got the results I wanted. Would also have to tweak the feeding chart to feed at a lower strength as my plants would almost always get burnt.

I was introduced to NPK Industries "RAW" nutrients by a friend that had recently switched to it and wouldn't stop talking about how easy it was to use and how good the results were. So being the person I am always looking to learn and improve I had to give these nutrients a try.

I started with just some of the products, I think it was just the Grow, Bloom, B-Vital and Calcium/Mag but by the time my veg was over I was so impressed I ordered the rest of the line and don't think I would ever stop using it.

I called my friend and thanked him, it was definitely a game changer, just like he said it is very easy to use. I follow their feed chart and I don't have to increase or decrease anything, I literally use what's recommended on the chart.

The Soluble Nutrients also means I get more for my money as I'm not paying for water like I would with some of the other brands and to top it off the great customer service is second to none. I placed an order in the height of the pandemic and Mark did everything in his power to keep me informed every step of the way ensuring that my experience was as smooth and stress free as possible.

I'll be a customer for life!!!

-Cheyne Harris



I own a hydroponics store in New Jersey and have taken his classes twice now, as well as my employees. It's great information for beginner or advanced growers in any medium to build on foundational knowledge of growing requirements and proper use of nutrients. Thanks Harley for sharing your experience in the industry!

-Master Growers Customer



Very helpful and informative. This course is wonderful and informative. So much to learn and apply to your garden!

-Master Growers Customer


Thank you so much for your help, Mark's kindness, generosity and willingness to help, is what this world needs more of. I have always been a LOYAL consumer, to the company that respects and treats customers with dignity, honesty and has an amazing product. I told him i was switching from Diablo nutes to NPK, im so floored and blown away by your company's ethics and incredible product, you now have a customer for life. Thanks, greatly appreciated.

-TJ Mills


Best courses I've found. Rated 5 out of 5.Harley Smith Master Growers Video Library Review.

Jeremy L.


I have contacted NPK industries now at least 10 times now, on separate occasions, with questions pertaining to different growing mediums.....

The staff there, specifically Leland, has demonstrated a great wealth of horticultural knowledge.   I have never been let down by one of his/their answers.   Even using their products in conjunction with my baseline, they were more than willing to help me figure out the most optimum approach....

They have always been available during business hours online, to chat, and have always responded within a few minutes! I have even spoken to Leland at lengths, via telephone, in order to more clearly communicate and work together as a team.  
I have been in the horticultural industry for the last 2 decades and very much appreciate talking to a person with a vast knowledge and strong background in the area...

You are the best Leland!!

Michael V.