The Agronomists, Ep 108: Navigating biological products with Mike Gretzinger and Connor Sible


Because biological crop products are neither fertilizer nor pesticide, there’s no requirement for efficacy proof before a product is released for commercial sales. So long as it doesn’t cause harm to the crop or pose an environmental risk, these biostimulants, stress supporters, and nutrient enhancers are largely sold on a buyer beware market.

But that’s not to say there aren’t some great products available, but understanding which classes of biological products seem to show the most promise and in what applications is still being worked out. To share some of what we do know, host Lyndsey Smith is joined by Mike Gretzinger of Farming Smarter, and Connor Sible, post-doc candidate with University of Illinois. They share their research and insight in to the best use of biological products in the video below!

Catch a new episode of The Agronomists Monday at 8 pm E!
Thank you to our sponsors: ADAMA Canada, RealAg on the Weekend, and Soybean School!


  • Connor’s team is planting soybeans this week, but we’re totally OK with that
  • What’s everyone working on? Connor is starting a seventh year researching biostimulants, biological fertilizers.
  • You’re going to hear this a lot: consistent results are difficult to achieve with some of these products
  • At Farming Smarter, they’re filling the need for independent evaluation of these newly-released products (largely unregulated in Canada, too)
  • Multiple sites, multiple products, on multiple crops
  • It all comes down to ROI
  • Where do biologicals fit? Do they replace a particular product?
  • It seems like there’s probably a new product every day
  • Start with answering, What do you want to change or improve on or make an adjustment with?
  • Biologicals don’t replace sound agronomy or the basics of good agronomy: focus on the right seed, a sound nutrient management plan, a pest management strategy  — then consider biologicals
  • How are biologicals like diet supplements? Mike explains. Plants are perfectly capable of growing without them, but maybe a process could be sped up, or done more efficiently
  • Let the record show, replacing an entire crop input is not what biological products can do
  • Lots of interest into residue decomposition and cycling, plus nitrogen and phosphorus management
  • Back to the question of consistency. Can you get consistency at one site, but not at different sites? Or will the same site even give you inconsistent results? The short answer is yes, the same site can give inconsistent results
  • Do biologicals work better in a drought?
  • Plants don’t know the forecast. It’d be handy to be able to prep a plant to anticipate a stress to come
  • Know your water! Quality, pH, minerals and what else you add can impact any product, biologicals included
  • How do you define biologicals? Bugs in a jug vs  biostimulant. They’re they’re not pesticides, because they’re not acting on pests directly, and they’re not fertilizers, because they’re not actually a direct application of a nutrient
  • How do we sort of separate the wheat from the chaff, if you will, and actually drill into what makes it a reasonable product ? Look for active ingredients, realistic promises, and some kind of guarantee or support for the product
  • Some companies and even farmers are willing to accept 70 per cent win rate,
  • Look for products that are one or two specific microbes where we understand what those microbes do
  • The good ones aren’t snake oil, they’re a viper lipid
  • Will we see some “add once or twice” and never again products?
  • Tillage, fungus, microbes — it’s a complex web
  • There are some of the living microbes that are not too synergistic with things like zinc and sulphur
  • What about WHERE and when the product is used? Are seed treatments better than in-furrow vs foliar?
  • Seed treatments have limited real estate but it’s on the seed
  • Think about product interactions too!
  • Understand how products work, i.e. phosphorus “liberators”
  • In thinking about adding a mycorrhizae product — does a later fungicide app cancel out the goodness?
  • We’ll have links to Farming Smarter and the University of Illinois work soon!

Wake up with RealAgriculture

Subscribe to our daily newsletters to keep you up-to-date with our latest coverage every morning.

Wake up with RealAgriculture

Other Episodes

The Agronomists (view all)Season 4 (2023) Episode 29

Please register to read and comment.

Privacy Preference Center


Necessary cookies help make a website usable by enabling basic functions like page navigation and access to secure areas of the website. The website cannot function properly without these cookies.

gdpr, __cfduid, PHPSESSID, wordpress_test_cookie, woocommerce_items_in_cart, woocommerce_cart_hash, wp_woocommerce_session, wordpress_logged_in, wordpress_sec, wp-settings, wp-settings-time, __cf_mob_redir, wordpress_cache, realag


Measuring interactions with the ads on the domain.



These are used to track user interaction and detect potential problems. These help us improve our services by providing analytical data on how users use this site.



Preference cookies enable the website to remember information that changes the way the website behaves or looks, like your preferred language or the region that you are in.

chartdefaults, comment_author, comment_author_email, comment_author_url
JSESSIONID, _os_session,anonymous_votes,csrf-param,csrf-token,user,user-id,user-platform,intercom-session,intercom-lou,intercom-session
personalization_id, tfw_exp


Register for a RealAgriculture account to manage your Shortcut menu instead of the default.