Welcome to Garden Myths – We are the Garden Myth Busters!
Our Goal: to provide correct gardening information and make you a better gardener.
Our Process: We research topics and examine scientific studies to bust gardening myths. Then we provide FREE blog posts.
Our Experience:
The author of most posts, Robert Pavlis, has 50 years of gardening experience, is an award-winning author of 11 gardening books, holds an M.Sc. in chemistry and biochemistry, teaches numerous gardening courses, and has written articles for many popular magazines such as Mother Earth News.
Robert’s Plant Science for Gardeners book won the Independent Publisher Book Award for Science in 2024.
In 2025, Roberts’ book, Food Science for Gardeners, won the International Book Award for the Home and Garden category.
Our Guarantee:
- The information on this site is more accurate than most other gardening sites. If you find an error and let us know in the comments, and we’ll correct it immediately.
- None of the information is created by AI – we prefer real people.
- All of the information is science-based.
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Start by selecting from one of these popular categories, and enjoy the site (click on image).
Robert,
Wow! You were great on “Nobody Listens To Paula Poundstone”! We have never grown great tomatoes. I can’t wait to read your book! Thanks for all the information!
Thank you – leave a note on the podcast to encourage them to have me back 🙂
In case someone missed the show, here it is:
https://paulapoundstone.com/podcast/ep-368-garden-time-with-robert-pavlis/
Hi Robert!
I just discovered you recently, and absolutely love your work.
Here are two questions:
1. What’s your opinion of Milorganite (6-4-0) as a general organic fertilizer?
2. What’s your opinion of Milky Spore for controlling Japanese Beetles gestation?
So appreciate your no nonsense approach.
Milorganite – nothing wrong with it on lawns and ornamental beds. I would not use it in a vegetable garden, but only because I want to be super careful.
Some biological controls do exist, however, they are not effective under Ontario’s climatic conditions. Milky spore disease, Bacillus popilliae, is a naturally occurring bacteria which was isolated in 1933 from infected grubs. Once attacked by B. popilliae, grubs slowly become weaker. This bacteria is not registered in Canada.
I watch many of your videos on you tube but lately there have been a lot of ads. I don’t object to the ads themselves but just now they showed a terrible scam ad with Mark Carney promoting a financial scheme. It’s one of those deep fakes ones and I’ve read about this particular one before. I’m doing some searching to try to figure out how to see your content without scams. I’m guessing that you have no control over the ads they show on your videos and it’s quite sad that you tube is allowing this.
Let YouTube know – I have no control over the ads they show.
Do you have suggestions for persistent weed control, specifically bindweed? I’ve seen it after covering an area with black woven weed block, coming up through 18 inches of black walnut chips, and under 5 feet of yard waste many years later. The plant spreads latterly several inches below-ground, by seeds, and by being left on the ground. So it can be spread by mowing, tilling and by birds. Just pulling it only slows it temporarily.
Let it grow to the flowering stage and treat with gylphosate (ie Roundup). It is not very effective, but will get rid of it over time.
Dear Robert,
I have no aversion to so-called synthetic fertilizer, however, in a recent purchase I noted that one of the ingredients was polymer coated urea. Do you know anything about what sort of polymers are used? Is it cellulose or formaldehyde or plastic or what? And what sort of residue does it leave in the soil? Is this cause for concern?
Thank you,
Claude
I don’t. I would not worry about it. I would expect they decompose in soil, slowly allowing more urea to be released.
Here is a review: https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/polymer-coated-urea
Robert, I’ve bought your Garden Myths Vol 1 and 2 and thought you had covered everything.
But if you’re ever short of myths to debunk, all you need to do is listen to a gardening radio show.
Yesterday I accidentally tuned in to a so-called “expert” who said that to keep potted plants alive outdoors in winter you should 1) put in 1/16 th inch (that’s 1.5 mm) foam insulation next to the pot on the inside 2) put mulch on top and 3) add plenty of nitrogen fertilizer since when mixed with water it lowers the freezing point.
Any fool should know that 1) the R-value of 1/16 inch of insulation is nil, 2) mulch has air spaces sounless it’s extremely fine it won’t insulate much, 3) without a heat source inside the pot, the soil will quickly reach air temperature, and 4) if you add enough fertilizer to measurably lower water’s freezing point you’ll kill the plant — just notice how dog urine kills grass.
What’s tragic is that some people actually believe thisclown.
I have no shortage of myths – I have about 350 that are partially started waiting for more work.
Insulation will never work because there is no heat source in a pot of soil sitting in a garage – as you say. This is a concept that very few of the general public understand.
Would love if you could do a comparison of straw and pine straw for mulch.
Also would like your insight on no-till gardening.
It is best for soil not to disturb it. Don’t compact it, don’t till it. Keep the ground covered with growing plants as much as possible.
Mr. Pavlis,
I am new to hydroponic gardening. Really new… as in yesterday. I also work long hours and don’t have the time nor huge space in my little shoe box apartment to grow many plants. I started with countertop hydroponic kits. I am having moderate success. However, I am getting so confused. Is the lighting good enough, did I plant the seed to low in the sponge, do I really need purified water, how often should I put nitrogen in the tank, is the unit large enough to hold plants? Could you throw me in the right direction? I watched a few of your videos on Youtube, and they are helpful… however, I am still not sure I am doing this “right.”
The topic is very confusing. The answers depend very much on which plants you are growing. Counter top hydroponics work fine for low light, smaller plants. They don’t work well for high light plants or ones that are large because they don’t provide enough light to lower leaves.
I did some testing that is still not published, and found that EC does not change very much as plants grow. It is best to top up the container with hydroponic fertilizer.
Hello! I have been enjoying your videos on Youtube- you have a wonderful voice which makes your videos not just informative, but a real pleasure. Keep up the good work!
And I was thinking about how potting soil could be labeled “sterile” when of course it isn’t. I found this definition for “sterilization” in Garden Terms by Amateur Gardening (published by Hamlyn,1995): “treatment to destroy weed seeds, insects, and fungal spores”. So that makes a bit more sense! :^)
Hi, I am interested in getting the purple tomatoes (GMO) developped by Cathie Martin showed in the interview with Nathan Pumplin that Robert Pavlis presented on youtube.
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