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Awesome Class. Instructor answered all of my questions. I’ve been growing, but making mistakes. Now I know what I have been doing wrong. The grow school is the best. Thanks
Greg P. -Upstate N.Y. 2023

If you are new to growing indoors or want to grow better, take this class with instructor David. You won’t regret it. He is very knowledgeable and easy to understand. Planted my first clones today. I’m excited!
Doug B. -Bend Oregon 2023

Thank you for all of the information we learned in our Online Grow101 class. Setting up our grow room now. Thanks again! Tom and Cindy
Thomas and Cindy B. -Atlantic City NJ 2022

Thank you (Instructor) David! I enjoyed you class and your input from your experiences. I learned some new things which I will put into practice. I’ve been growing for two years now and my last grow went wrong. Through your class I figured out what went wrong, so thank you very much for that. I’m starting a new indoor grow and I will let you know how it goes. 
Anonymous -Portland OR 2022

Took my online live course yesterday. My first time taking a course of any kind since high school 30 years ago. The instructor made everything clear in an easy to understand way for me. The e-book looks great, I’m excited to start reading. And growing.
Lane J. -Washington DC 2022

I bought this course for my husband as a Christmas gift. He loved it. We started some seeds last week and are looking forward to this growing experience. Thank you for taking the time to explain everything in detail.
Joanie K. -Enid OK 2022

If anybody is trying to learn how to grow indoors in soil, I suggest you take this class. I took an online course with an instructor, and he answered all of my questions. This is great. I finally set up my grow room and I’m ready to go. Wish me luck.
Doug D. -Idaho Springs CO 2021

I have been trying to learn cannabis horticulture to better my chances of getting a job in the industry here in Colorado. This class helped me get a better than entry level position at a large grow. I have been there about six months so far, and they just offered me a supervisory job. Thank you for The Grow school.
Justin T. -Glendale CO 2021

Cannabis is finally legal in my state! I took this class because I want to grow my own and save money. I harvested my first 3 a weeks ago. Everything came out perfect. Thank you grow school!
Steve B. -Fonda NY 2021

Thank you for this very informative class. I have some experience growing, and I will add these techniques to my repertoire. Very enjoyable and the instructor was very well spoken. Highly recommend.
Gary S. -Chicago IL 2020

My class was exactly what I needed. There is a lot of conflicting information out there about growing successfully, indoors and the instructor guided me through the techniques that work the best. I am excited to start legally growing!
Craig N. -Portland OR 2020

Thank you.
Josh L. -Fowler CO 2019

Very happy with the info.
Jeremy B. -Ontario Canada 2018

I attended an online class in 2017 taught by David. I had been growing for five years when i took the class, and I still learned some very valuable information. I will be recommending this class to my friends.
Mark P. -Sacramento CA 2018

I was extremely happy with all the excellent information that I got in my grow class. The garden support has helped me with a few issues that I could never solve before. I’m very happy.
Avery K. -Vista CA 2018

Excellent class.
Krista L. -Grants Pass OR 2018

Thank you for the informative class. I have been trying to learn on my own from the Internet for a few years with little success. Your class taught me what will actually work.
John C. -LaJolla CA 2017

Just checking in! It has been almost 3 years since class, time flies! I learned so much in class. I have been working all year at Strainwise (which has 9 dispensaries) in the 60,000 sq ft cultivation warehouse, doing every job, but mailly in the clone department. Thanks for the class, so important to get me started and obtaining a job. Perhaps, next year, my own greenhouse facility!
MONA G. -Denver, CO 2017

I attended your class in August 2015. I just want to say that I got a job at Terrapin Care Station in Boulder! The medical warehouse. I’m so excited about this! It all started for me with The grove school, I appreciate your attention.
LEO C. -Boulder, CO 2016

Instructor David had the ability to present complicated scientific growing information, in a simple and easy to understand way. That helped me easily understand what he was talking about. I now have a much better sense of the big picture common in a great sense of covenants for growing.
RAY G. -Denver, CO 2016

Incredibly informative class. Tons and tons of info. Can’t wait to put the info to use!
Lauren B. – Denver, Colorado 2016

Instructor was very knowledgeable and presented lots of good information on the cannabis growing process.
Kim L. – Denver, Colorado 2016

I’m extremely pleased with the information contained in your online self paced 12 hour class. I’ve only completed 10 hours so far but I will be finishing today. I do have seven years of indoor experience throwing in a couple hundred plants under my belt, and I still learned something from each video and will spread the word! Thank you guys so much for the wealth of information and easy access to it.
Jeremy D. – Hamilton, Ohio 2015

The Grow School in Denver is very professional and knowledgeable. I highly recommend them for growers of all skill levels. They have an excellent garden support team. Overall AAA+++ experience!
Captain C. -Sartwell, MN 2015

(David) You’re an awesome teacher! I’m looking to start a cannabis and CBD edibles company here in DC.
Holly D. – Washington, DC 2015

I attended David Degraff’s course Grow 101 in March in Washington DC. I believe it was a very valuable course. Mr. Degraff obviously has decades of experience. What I thought was extremely important was how Mr. Degraff was able to communicate technical concepts into a language that I was able to understand. He made this scientific discipline incredibly accessible. I look forward to taking more courses and learning how to implement his technical expertise. If you have an interest in this field of study and The Grow School is touring through your region, I highly recommend you consider attending a class.
Anonymous – Washington DC 2015

I attended and completed the march Washington DC grow 101 class. The presentation style was really helpful to translate technical concepts into layman’s (me) understanding. The e-book is a terrific resource.
Gary C – Washington DC 2015

First let me tell you how much I enjoyed The Grow School. You have definitely done your homework and it showed. Thanks for a most informative and educational six hours on Saturday. You have a tough job. You have to get people up to speed not only on botanical theory, but plant pathology, genetics, propagation, photoperiodism, and growing climate – each of which are 4 semester hour great undergraduate courses. I have put it with my college texts as a reference volume. Basic theory I knew, but the nuances of all the disciplines as they specifically relate to cannabis are a quick to the point reference. The handbook alone is worth the cost of the whole course. Again, thanks for a most interesting Saturday.
Robert E. (Master’s Degree Horticulture) Alhambra Illinois 2014

I loved the class, it was very informational. I am going to keep educating myself. Thank you for the great experience. Jesus G. – Pennock, MN 2014

Hi! Hope everything is good. Now it’s getting a little bit colder here in Brazil. The summer is going away! I am in week 2 of flowering. It’s looking great! Take care!
Bruno B – Rio de Janeiro, Brazil S. A. 2014

I learned more in the elevator on the way up to my class at The Grow School, then I did in that entire other “Grow University” class I took in Denver….
Andrew K – Fort Myers Fl 2014

I want to thank you guys for the excellent class given. It was a great experience and instructor David was extremely helpful and knowledgeable.
Katy C – Aurora CO 2014

I attended your class on 5–18. We have followed your instructions from the Grow School handbook. We have 6 beautiful plants! Your class was well worth the cost! Thank you
Mike N -Conifer CO 2014

Just wanted to thank you for the great class yesterday.
Michael B – Evergreen CO 2014

Just a quick note to thank you for your time. The knowledge we got today will prove to be invaluable in the future. Tom F. And Mike M. – Aurora Colorado 2013

You are awesome! Thank you.
Annette L (Disabled Veteran) –Indianapolis IL 2013