Despite the best efforts of gardening educators to debunk poor gardening advice, bad information continues to be shared online and elsewhere by well-meaning, though ill-informed, gardeners. To keep up the fight against bad gardening tips that persist, this week I am sharing once again my conversation about decoding gardening advice, with Dr. Jeff Gillman, a horticultural scientist who puts common gardening recommendations to the test to determine what’s really backed up by science and what advice is a waste of time — or even detrimental.
Jeff is the director of the University of North Carolina Charlotte Botanical Gardens and is a former associate professor in the department of horticultural science at the University of Minnesota. He holds advanced degrees in both entomology (the study of insects) and horticulture and is the author of five books on gardening and the environment, including the book that inspired this episode, “Decoding Gardening Advice: The Science Behind the 100 Most Common Recommendations.”

Dr. Jeff Gillman is the director of the UNC Charlotte Botanical Gardens and author of the book “Decoding Gardening Advice: The Science Behind the 100 Most Common Recommendations.” (photo: Courtesy of Jeff Gillman)
From the use of landscape fabric, fertilizer and mycorrhizae, to tree topping and best practices for seed starting, watering and pest control, in our discussion, Jeff exposes which gardening advice is debatable, at best, and just plain wrong, at worst.
If you haven’t listened to this episode yet, you can do so by scrolling up the page and clicking the Play button on the green bar. For a complete recap of the episode, view the show notes from the original airing.
What common gardening advice do you find questionable? Share with us in the comments below.
Links & Resources
Episode 007: Organic Weed Control with Jeff Gillman
Episode 008: Organic Pest Control with Jeff Gillman
Episode 009: Organic Disease Control with Jeff Gillman
Episode 034: Gardening Myths BUSTED, Pt. 1 with Linda Chalker-Scott
Episode 039: How to Start Seeds Indoors: Digging Deeper, Pt. 3
Episode 048: The Simple Science Behind Great Gardening, with Lee Reich
Episode 053: Waterwise Gardening With Nan Sterman
Episode 067: Predatory Beneficial Insects: Feared Foes of Garden Pests, Pt. 1
Episode 068: Top Predatory Beneficial Insects and How to Attract Them, Pt. 2
Episode 069: The Fascinating Facts Behind the Plants We Eat, with Jeff Gillman
Episode 070: Decoding Garden Advice: Good, Debatable or Just Plain Wrong, with Jeff Gillman
Episode 162: Plant Disease Fundamentals – Understanding the Basics and Beyond
joegardener Blog: The Numbers on Fertilizer Labels, What They Mean
joegardener Online Gardening Academy™: Three popular courses on gardening fundamentals; managing pests, diseases & weeds; and seed starting!
joegardener Online Gardening Academy Essential Gardening Fundamentals: The basics on healthy soil, planting, watering techniques, composting, raised bed and other gardening methods, fertilizer, the many benefits of mulch, and more.
GGW Episode 314: Just Because It’s Organic
GGW Episode 419: Garden Myths 2.0
GGW Episode 618: The Truth About Organic Gardening
“The Truth About Organic Gardening: Benefits, Drawbacks, and the Bottom Line” by Jeff Gillman
“The Truth About Garden Remedies: What Works, What Doesn’t, and Why” by Jeff Gillman
Exmark – Our podcast episode sponsor and Brand Partner of joegardener.com
Rain Bird® – Our podcast episode sponsor and Brand Partner of joegardener.com
Park Seed® – Our podcast episode sponsor and Brand Partner of joegardener.com – Use code Joe20 for 20% off your next order
*Disclosure: Some product links in this guide are affiliate links, which means we would get a commission if you purchase. However, none of the prices of these resources have been increased to compensate us. None of the items included in this list have any bearing on any compensation being an influencing factor on their inclusion here. The selection of all items featured in this post and podcast were based solely on merit and in no way influenced by any affiliate or financial incentive, or contractual relationship. At the time of this writing, Joe Lamp’l has professional relationships with the following companies who may have products included in this post and podcast: Rain Bird, Corona Tools, Milorganite, Soil3, Park Seed, and Exmark. These companies are either Brand Partners of joegardener.com and/or advertise on our website. However, we receive no additional compensation from the sales or promotion of their product through this guide. The inclusion of any products mentioned within this post is entirely independent and exclusive of any relationship.
0 Responses to “175-Decoding Gardening Advice, With Dr. Jeff Gillman – Encore Presentation”
Learn something new again. Fertilizing in the fall is okay and recommended. Who knew! I knew fertilizing the lawn in the fall was important but didn’t know it was okay for the landscaping.
That one is counter-intuitive to me too, Julie. I remembered the first time I learned that, it really surprised me. Always something new, indeed.