Friday, March 29, 2019

Impatiens Downy Mildew

Friday, March 29, 2019

During the past year and especially last spring when gardeners were thinking about what annuals they usually grow or purchase for their gardens, I mentioned that progress was being made with Impatiens Downy Mildew which in previous years knocked out impatiens in much of the East Coast but also in many points worldwide. I mentioned how the plant industry was recommending many other plants as substitutes which like impatiens could tolerate some shade. New Guinea Impatiens were recommended as were various seed begonias and coleus.

I am offering this research update because I don't want to leave folks thinking that the problems are gone and impatiens purchases will be completely fine this year. Obviously, there is a wide chain of seed and there is always the possibility that seed that grew plants that were susceptible to IDM is still out there and might be used. 

This article from one of Ball Seed's publications says that things are looking better in the research arena but final research and testing, eventual seed production, growing and testing, are still required. I was interested to see mentioned that the disease was in the soil for a long time but only in very recent years did it begin to multiply. I will never be a scientist but I do know that half a degree in temperature change has taught me how quickly new insects make their way to Vermont and invasive plants or plants we never before saw as invasive are suddenly overtaking areas where we previously planted them intentionally after purchasing them from dependable nurseries and greenhouses we had used for years. 

Check out the news release and keep a good eye on all your plants!

George Africa
The Vermont Gardener

Bumblebee Watch

Friday, March, 29, 2019

It might be strange for me to be talking about bumblebees when there is still 4 feet of snow on the ground outside my office window but bumblebees are a bee I will be studying this summer. I have always been interested in bumblebees and for years at the flower farm, I have intentionally grown a few rows of Helianthus 'Lemon Queen' which appears to be a regional magnet for various pollinators including bumblebees. I joined up with the Xerces Society last month and just noticed a blog about a study being conducted by York University in Toronto, Canada. Part of the project is identifying Pacific Northwest bumblebee species in the states of Washington, Oregon and Idaho.  Long haul from Vermont and the east, right????

Take a look at and click on the Bumblebee Species tab and when it opens, on the top right is a drop down for bee species. As you click through each one you'll notice a map of the Continental US at the bottom which is shaded for each bumblebee's geographic presence. Surprisingly, many of the bumblebees which live in the west also live in the east.

My experience so far is that from year to year there are more or fewer bumblebee species at the flower farm. This past summer it was exceptionally dry and the bee populations were very high in number. This was true of all insects including butterflies and moths. During springtimes when snowmelt has been slow and snow was deep, to begin with, bumblebee numbers have been down. I have always attributed this to rodents seeking out queens and eliminating the opportunity for a ground hive early in the summer season. I may be wrong on that but Spring 2019 will be a great year to test the theory after all the snow we have received. If you notice a queen flying around your gardens, check the species pictures and try to identify which one you have.

Writing from the mountain above Peacham Pond where +40 evening grosbeaks are cleaning up birdseed right now.

George Africa
The Vermont Gardener
On Facebook as George Africa and also as Vermont Flower Farm & Gardens
Just today wrote about migratory birds returning to western Vermont