Gardening Ground Truths: Revisiting “Finding Credible Sources”

This is the time of year gardeners begin to dream about spring and summer and the possibilities for their landscapes, vegetable gardens, and containers. The old adage “fail to plan, plan to fail,” rings true in gardening. In addition to keeping detailed records annually about your garden, doing your homework both upfront and along the way is key. But not all research–especially on the internet–is created equal. As you begin planning your 2023 garden, it seems like an excellent time to revisit Ann Barnes’s 2017 article on conducting quality scientific-based research and best practices for your own experimentation. In keeping with Ann’s suggestion to look for the latest information, we’ve included updated links and resources.


(Image credit: M. Heigel; North Carolina State University)

By Ann Barnes, EMGV

When looking for answers to gardening questions, the internet is a fast and convenient place to search. It is important to remember that anyone can post content online, and there is no review process to ensure information on every website is correct. Extension Master Gardeners recommend unbiased, research-based information. There are many websites that claim to provide gardening information. Not all of them can be considered credible.

The “Who, What, Where, When, Why, and How” of Finding Trustworthy Information

Who are the authors, and for whom are they writing? Are they experts in a scientific field related to gardening, affiliated with a university, or trained Master Gardener Volunteers? Do the authors cite sources and/or provide links for further reading, and are those links to research-based sources? Does the author (or the entire website) seem to have an agenda or are they presenting unbiased information? Are the authors even listed, or does the article appear to be shared from some unnamed source? If you can’t determine who wrote the article (individual or organization), how can you know if the author is a credible source?

If a light switch in my house wasn’t working, I would call an electrician. Advice from my pharmacist or from a blogger who posts “home hacks” would not give me as much confidence as advice from an expert. The same should hold true for gardening – consult an expert in agriculture for the most reliable answers to questions about growing plants.

What: There is a science to growing great plants, so look for answers on sites that are research-based. There should be links to studies that support recommendations. When applicable, both organic and chemical options will be discussed in an unbiased manner. Keep in mind that natural doesn’t always mean safer or more effective, and not everything presented as a fact on the internet is true. Always check sources, particularly when you see a “scientific fact” shared as a meme or a link on social media.1

Credible sources don’t promise miracles or promote home remedies over conventional growing practices. Credible sources aren’t trying to make a sale or to criticize an existing product. Credible sources typically won’t promise that “your jaw will drop.”

Where: Check the URL of sites in your search results. Sites that end in .edu or .org (education or organization sites) are more likely to contain unbiased and research-based information. Master Gardener Volunteers are affiliated with Cooperative Extension, whose purpose is to share information obtained from research conducted at land grant universities, such as North Carolina State University (NCSU) and North Carolina Agricultural and Technical State University (NC A&T). Therefore, we recommend searching extension websites. Sometimes answers can be found at any state’s land grant university, but keep in mind your USDA Plant Hardiness Zone when searching for information about specific growing questions. For example, the average last frost date in the Triangle is much earlier than the average last frost date in Wisconsin, so you would need to look closer to home when searching for when to plant your tomatoes.

Here’s ONE WEIRD TRICK for finding all the garden answers you need:

Bookmark this link, and you can search like a Master Gardener:

This will take you to a custom search engine that will only search Cooperative Extension sites. If you’d like to broaden your search beyond land grant universities but still search only for sites associated with academia, use your favorite search engine and follow your search terms with “”. For example, when researching how to grow tomatoes in containers, type: Tomatoes in containers in your browser’s search bar.

When: Does the article have a publication date? Science is an ongoing process and recommendations sometimes change due to new research, so it is best to use fairly recent sources. If there are links, are they current? Broken links may be a clue that an article is older.

Why: What is the purpose of the site? Is it providing unbiased, research-based information? If it isn’t a university website, is it selling a product? Does the site have bias towards or against a certain way of gardening? A site promoting a product has a goal of making sales, so there will be a bias towards their product. Similarly, articles published by authors with a general mistrust of agricultural chemicals will show a bias towards organic-only solutions. While biased sites may provide information that is correct, they may not be showing you all your options or the data behind these options.

Finally, there are the click bait articles, those amazing home remedies that are supposedly better than commercially available products, full of “facts” that sound miraculous but often aren’t true. The same information, word-for-word, may be posted on multiple websites. Click bait sites are designed to get people to click on them; it’s as simple as that. They don’t have to cite sources, use research methodology, or even be scientifically accurate. There is a lot of bogus science out there, and some of it looks pretty believable if you don’t check for source material.

Debunking some internet myths about gardening:

How: Good science is based on experiments that follow the scientific method, in which a scientist tests his or her hypothesis in a series of experiments. If I wanted to test Grandma’s Homemade Weed Killer to see if it was as effective as a leading Big Agricultural Product, I would need to conduct tests using each product on similar weeds in similar conditions, then compare results to see if there is a statistically significant difference in the two.

If I simply sprayed weeds with the Grandma’s Homemade Weed Killer, found some dead weeds, and announced that this remedy was safer and more effective than the Big Agricultural Product (without comparing the two in well designed experiments), my claim would be invalid, since I didn’t test for safety, nor did I compare the two weed control products. Claims need to be backed up with experiments.

How to design an experiment:



1–Many botanical gardens, cooperative extension offices, and master gardener volunteer programs now have a social media presence on apps like Instagram and Facebook where they present videos and links to solid information. Make sure you are following the organizations’ official accounts. You can follow Durham County Extension Master Gardeners on social media at @durhamncmastergardeners on Instagram and NC State Extension Master Gardener Volunteers, Durham County on Facebook.

Resources and Additional Information

Three great examples of university-based sites with searchable gardening information appropriate for our Plant Hardiness Zone are North Carolina State’s Plant Toolbox, NC Cooperative Extension, and Clemson University’s Home and Information Garden Center. See links to these amazing resources below.

Botanical gardens, arboretums, and gardening non-profit organizations such as state native plant societies (.org or .edu sites) can be excellent and trusted resources for gardening information. The American Horticultural Society website, while not a complete listing, has geographic search features for master gardener programs, plant societies, and over 345 North American botanic gardens, including links to their websites. Some great North Carolina-based garden sites that have a plethora of plant information on their sites include the J C Raulston Arboretum, North Carolina Botanical Garden, and the Sarah P. Duke Gardens.

Look for Extension Master Gardener training materials online. For example, North Carolina State University and NC Cooperative Extension provide full online access to their entire gardener handbook, the foundation for all Master Gardener Volunteer instruction.

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