Now that poinsettias are safely tucked into their prop trays and the threat of Erwinia (Pectobacterium) is almost over, it’s time to think about other Poinsettia issues.
Root rots, nutritional issues, environmental stress and PGR mistakes can all be costly in this high-value crop. Read on for common pitfalls and how to avoid them.
Continue reading “Poinsettia Prep Refresher”
Powdery mildew on cut roses in Ontario.
With May’s weather continuing to be up and down, humidity control is a problem in the greenhouse, meaning Powdery Mildew (PM) is too. This pest is rearing it’s ugly head in crops like Kalanchoe and Dahlia.
We won’t cover the basics of PM here: biology, spread and prevention were covered in a previous post. Instead, we’ll focus on monitoring, and which control products to use once you’ve found an infection.
This post was written with help from Plant Pathologist Ann Zemke of the Chase Research Group.
Continue reading “Powdery Mildew Being a Pain? Effective Products for PM Relief.”
Wilting of a poinsettia plant on a bench of otherwise healthy plants could be Pythium root rot. But then again, it might not…
From now until mid-November is when you’ll most likely see plant losses in poinsettia due to severe wilting. These losses can be considerable: anywhere from 2-15% in Niagara operations in past years, with disease pressure seeming especially high this year.
Pythium may be considered the most “likely” culprit in Poinsettia in this area, but this isn’t always the case, and misdiagnosis can mean wasted fungicide applications. Read on for a list of likely suspects and appropriate control measures.
Continue reading “Fainting “Freedom Red”? Wilting “Whitestar”? Potential causes of Poinsettia collapse, solutions, and the importance of testing.”
Rooted Calibrachoa plugs. Photo from jparkers.co.uk
It’s that time of year again, when unrooted cuttings or rooted plug trays of Million Bells (Calibrachoa) are first arriving in the greenhouse.
When they go right, Calibrachoa are a relatively easy, staple spring crop. However, when million bells go bad, they go bad BIG time.
To help your crop turn out this year, Chevonne and I have compiled some info on how to prevent and deal with common issues in Callies.
Continue reading “Managing Million Bells, 2017 Updates”
For those of you that missed my webinar on “Thrips Control: from Propagation to Pocketbook”, it is now available for free on the Greenhouse Canada Magazine website.
Keep reading for more details and a link to the talk. Continue reading “Webinar Detailing Thrips Control Strategies Now on the Web.”
Western flower thrips adult on an open Mandevilla flower. Photo credit: Caitlin MacDonald, USEL student.
Now that the warm weather is finally upon us, it’s time to start worrying about thrips control.
What we’ve learned over the years is that pesticides just don’t cut it – the only reliable chemical for western flower thrips in Ontario is DDVP, which requires constant application. This means biological control is your best bet. Here’s a summary of the most effective tools, tricks, and timing, to ensure your biocontrol dollars are well spent.
Continue reading “Ramping up thrips biocontrol BEFORE they get out of control!”
Entomopathogenic nematodes – used to control fungus gnats, shoreflies and thrips – are often a “gateway bio” into biocontrol use in greenhouses. This is because not only are they effective and easy to use, but they’re generally compatible with insecticide use. Readily applied with regular spray equipment or through drip lines, nematodes can even be tanked mixed with pesticides to save on labour costs.
In this post, I’ll share some of my research at NC State, looking at which commonly used pesticides in Canadian and U.S. greenhouses are safe to use with nematodes.
Continue reading “Can you safely mix nematodes and pesticides?”