Late Blight Arrives!

Late Blight has arrived at Pennypack Farm, the CSA I belong to. Here is the news sent out by email yesterday from the farm...

Late Blight Arrives in Horsham
By Farmer Andy

Recall the horrible Irish potato famine of the mid 1800s - when thousands starved and countless others fled for a better place to live (and eat). None of us were around at that time, but by all accounts this was a disaster of the highest order. Basically, much of Ireland had become dependent on potatoes as their food staple and when the crop failed one year, there was not much to eat.

The cause of this historical famine is known as late blight. It is a fungus that attacks potatoes and tomatoes, and over a period of several weeks, kills its host and launches spores into the air to find new victims. It spreads quickly and thrives under cool, moist conditions. The kind of conditions we have been experiencing throughout the spring and into the summer.

There is no sliver bullet for late blight. Conventional growers use a number of highly powerful and toxic synthetic fungicides to stop the spread of the disease, but for us in the organic farming world, there are few options. We must remove any infected plants and treat all others with an organic copper fungicide, which helps slow the disease. Hot, dry weather, the kind we usually have at this time of year is our best ally. But, in the current moist conditions, this fungus is thriving.

We have been vigorously scouting our tomato and potato crops this week and removing diseased plants. So far, we have not found any evidence of the late blight on our potatoes, but it has infected approximately ten percent of our tomato crop. These plants have been disposed of and all others treated with the copper.

At this time we simply do not know what affect this will have on our overall tomato crop. I would expect, at the very least, a smaller harvest than in past years and it is unlikely that we will be able to offer tomato canning shares this season.

However, we are hopeful that by removing the diseased plants and treating the others, we will still have a reasonable tomato harvest in the coming weeks. We will keep you posted on updates on this situation as they become available. Thank you in advance for your patience and understanding.