Choose the right soil analysis for in-ground cut flowers

This post was contributed to by Lauren Vanderlingen, OMAFRA Summer Student and Christoph Kessel, OMAFRA Soil Fertility Specialist – Horticulture.

If you are using Saturated Paste Extract (SPE) to assess soil nutrients for in-ground grown cut flowers, you may be underestimating plant available nutrients and applying fertilizers that aren’t needed.

Many greenhouse growers use SPE analysis when testing growing media in the greenhouse for nutrient levels. Typically, SPE tests are used in soilless or peat-based growing substrates, the kind we usually see used in potted plant production. However, if you are growing cut flowers in a mineral soil, either in the greenhouse or outdoors, SPE is not giving you a complete report on nutrients available to your crop.

Both greenhouse and outdoor soils that produce cut flowers should be tested on a regular basis.

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Which Pesticides are Effective for Whitefly?

Bemisia 4_SJ — Whitefly – especially *Bemisa* whitefly – are STILL one of the hardest insects to control with pesticides in the greenhouse industry,

Efficacy trials are key to keeping growers informed about which chemicals currently work and which don’t for Bemisia whitefly.

Entomologists at the University of Maryland and Delaware recently did such a study, and included newer pesticide registrations. If you missed the article in the July issue of Grower Talks magazine, keep reading for the link to their results and a Canadian take on the study.

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Garden Mums – 2019 Production and Protection Tips

This post was contributed to by Drs. Sarah Jandricic and Chevonne Dayboll.

Summer is in full swing, and so too are garden mums. As you get ready for the next few months, here are a few tips to keep your crop on track.

Drip line irrigation can be a more efficient way of delivering water and nutrients to outdoor crops.

Irrigation method matters!

There are plenty of options for irrigation in potted outdoor crops, but not all are created equal if you are trying to maximize your water efficiency. Overhead irrigation by boom, or sprinkler is not efficient if your pots are not spaced tightly. Canopy sizes in the later months of production may make this impossible, especially if you choose to go with final spacing when pots first move outside. These methods of irrigation can also lead to pots that are too dry (not watered) or too wet (over watered). Plants can only use water that makes it into the pot, so low volume drip line or tape is a more effective way to delivering usable water to your outdoor crops.

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99 Poinsettia Problems: Your Monthly Scouting Guide

JF14 — This post on poinsettia problems was contributed to by Drs. Chevonne Dayboll and Sarah Jandricic.

Okay, so Poinsettia don’t really get that many problems. But when issues arise, they can hit a crop fast and hard. Whitefly, Lewis mite, root rots, and nutritional issues can all quickly derail a quality crop.

Here’s a month by month guide on what you should be looking for to prevent small problems from becoming big issues.

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Now’s the Time for Whitefly Prevention: Registered Products for Poinsettia Dips

OLYMPUS DIGITAL CAMERA Here in Canada, we’ve been talking for years about research on the highly effective method of dipping your poinsettia cuttings in low-risk pesticides to reduce starting whitefly populations.

Thanks to Dr. Rose Buitenhuis (VRIC), Cary Gates (FCO) and BioWorks, the label for BotaniGard WP has now officially been expanded to include dip applications. This now adds to our arsenal (see below for more dip products).

Read on for the current BotaniGard label and how dipping can help improve your Bemisia whitefly program this year, whether you’re using pesticides or biocontrol.

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Poinsettias: To Spray or Not to Spray, that is the Question

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T’is poinsettia sticking season once again, and the question always comes down to the same thing: do I use chemicals to control Bemisia whitefly and hope it works this year? Or do I switch to biological control? Here we show some head to head comparisons that can help you decide.

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2018 Poinsettia Wrap Up: Whitefly and Pesticides

Bemisia 4_SJ As suspected, it’s turned out to be a heck of year for Poinsettia. Many growers faced Erwinia, others had rooting issues, and all faced significant pressure from Bemisia whitefly from infested cuttings.

As the time approaches for the plants to go out the door, this post covers whitefly control successes/failures in 2018, and what to do with remaining populations.

Whitefly and other poinsettia issues are also being discussed at the Niagara Poinsettia Open House on Tuesday, November 20th. This will take place at Jefferys Greenhouse (Plant II) starting at 10 am. See the latest issue of Greenhouse Canada Magazine for more information (pg. 28). Hope to see many of you there.

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Which Thrips are in Your Flower Crops (Part II): How to ID and Control Onion Thrips

Thrips-tabaci-female-1-1024x683 — Thrips tabaci, or Onion thrips. Photo courtesy of Thrips-ID.com.

If you were at the Canadian Greenhouse Conference (or are regularly reading this blog!) you’d know we’ve recently identified Onion thrips as a pest of floriculture crops in Ontario (see this post).

Outside of Ontario? Well, this still may apply to you, as a recent study in France also indicated that up to 47% of pest thrips in floriculture greenhouses were Onion thrips. So, this issue could be wide-spread.

My last post covered the extent of the problem in Ontario’s industry. This post will help you identify if YOU are dealing with Onion thrips (OT) along with Western flower thrips (WFT), and what to do about it.

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Which Thrips Are in Your Flower Crops: When Paradigms Shift (Part 1)

WFT on hibiscus_Caitlin McDonald_1 Up until this point, most of Ontario floriculture growers (and me!) assumed the only pest thrips we were dealing with was Western flower thrips (besides Echinothrips in a few crops like gerbera and poinsettia).

But a survey conducted in major commercial operations in 2016-2017, AND recent outbreaks of serious damage have proved us wrong. (You know what they say about assuming!). Keep reading to find out the truth about thrips! Continue reading “Which Thrips Are in Your Flower Crops: When Paradigms Shift (Part 1)” →

The “Tipping Point” for Whitefly Control in Poinsettia

If you started out using biological control in your Poinsettia crop this year, you’ve now reached the crucial tipping point for whitefly control decisions.

Based on the size of your whitefly population in mid-late September, your populations could end up too high by November to effectively control. Ultimately, this could affect sales.

So, do you keep going, and hope for the best? Or switch horses mid-stream, and start using chemicals? To help you determine which is the right call, keep reading.

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