I PRE-ORDER CERTAIN ANNUALS—reserving whole flats of favorites with my local garden center to make sure I won’t get shut out. Normally that early commitment includes a favorite peachy-colored impatiens, but this year, I’m not so sure. Impatiens downy mildew ravaged the popular bedding plant in many parts of the country last year, so I asked Margery Daughtrey, a plant pathologist and senior Extension associate with Cornell University, what the early line is from where she sits in her Suffolk County, Long Island, lab–and some substitutes I might consider for that annual order of mine.
First, a recap of what Impatiens downy mildew (the fungus-like Plasmopara obducens) looks like:
Did your impatiens seem to collapse in 2012? Early signs of infection may have been leaves that looked yellowish, as if the plant needed feeding, or foliage that curled under or seemed to wilt. Sometimes, a white material (the downy mildew) is visible on the undersides of leaves. Eventually, plants may defoliate, drop their flowers, and basically collapse. The fungus loves moist conditions and cool nights in particular. Particularly disturbing: symptoms happened earlier last year than before—as early as June.
The disease, which attacks Impatiens walleriana (the species our common shade-garden choice is bred from) showed up in 2012 first in Florida and later in the Mid-Atlantic, the Northeast, and even Utah and the West Coast. By Daughtrey’s count, 35 states had at least one case of the disease in 2012, and some Canadian provinces as well.
my q&a with cornell’s margery daughtrey
Q. I’ve been watching the trade publication “Greenhouse Grower” for news on impatiens downy mildew, and in a December article, you said that growers are of course well aware of
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You may have already noticed that rice prices are higher than normal, which is largely due to the impacts of the war in Ukraine and erratic weather for the leading global suppliers of the grain. Now, India, the world’s largest exporter of rice, just banned nearly half of its overall shipments in order to reduce its domestic prices following heavy rains, which impacted the rice harvest. You might be asking, “What does this mean for me?”—we’ve got you covered. The good news is, if you’re worried about how the ongoing global rice shortage could impact your plate, you’re not alone, but you don’t need to panic.
I am miffed that the Royal National Rose Society has gone into administration (May 2017). Originally formed in 1876 it owns land in St Albans but finds annual running costs onerous. As small compensation here are details about a couple of charitable red roses.
The dry weather has cause a lot of problems with moldew. (I should have said mildew but that is a Freudian slip I will leave in.) The worst affected in my garden is an early flowering clematis but this rose stem is not far behind.
Flower spikes can reach over 6 foot and when massed together at the back of the border look really special. Delphinium are worth the effort to grow successfully and here are some tips to help.
Mildew is a white powdery fungus that looks unsightly on these leaves. Mildew is a sign of stress in a plant and usually arises from damp air with poor circulation. It is prevalent in my garden now Autumn is here in force. It is of less concern in winter as the cold will take care of the current problem until next year at least.
If gardeners have left wet leather gloves or shoes in a mild garage since summer they may now be covered in a white dusty substance that is powdery mildew. Powdery Mildew can affect many garden plants and it is especially vexatious on Gooseberries, Roses and Peas. The greying of leaves leads to yellowing, distortion and falling, it is unsightly and damages crops. For help understanding mildew read these tips.
Mildew is an airborne fungus that requires wet weather and warmth to come to life. It is most visible during spring and autumn as the winter is too cold and in summer it may be too hot. The wetter spring and autumn is when the white powdery mold-like mildew shows up most.
Turfgrass is the largest or one of the largest crops in America, and you can’t eat it or wear it. In addition, it requires water, fertilizer, and a tremendous amount of energy to maintain. Given that many of our lawns are high maintenance, some folks might consider reducing the size of their lawn by using native grasses and flowering perennials in borders instead. Here are a few ideas for layout and planning a border meadow. Generally, the plants are not over 3 feet tall, and ornamental grasses are the dominant group. However, upon closer inspection, you will also see groups of plants from other families interesting to people, pollinators, and birds. They support wildlife and may reduce the homeowner’s use of irrigation, fertilizer, and pesticides.
Basil (Ocimum basilicum) is one of my favorite culinary herbs. It’s relatively easy to grow and is available in many cultivars, some of which are quite decorative. A member of the mint family, it’s a vigorous grower that may leave you wondering how to use it all. Here are my five favorite uses for this spicy herb.
“The biggest problem I encountered was with the Phlox I planted,” Dan wrote. “The leaves developed a terrible fungus and it slowed its growth terribly. When I first spotted it, I did some research and decided to use an organic fungicide. That worked alright, but the fungus came back. Then, I tried an organic remedy I found on the internet: spraying with a milk solution. That worked less well. The poor plants were so overcome with the black fungus that they eventually withered without flowering late in the summer. I finally cut them down. Now they are starting back with strong green growth and I’m pleased, but I wondered if you had any advice for treating Phlox fungus.”One of the best non-chemical ways to deal with powdery mildew, I replied, which Phlox paniculata is so prone to in our humid summer
IT’S A SIMPLE QUESTION: DO YOU LIKE TO MOW? Unless, of course, like me you have a love-hate thing going with mowing. I am always irritated that there’s mowing to be done.