3/29 Whoa! Bugs in the Greenhouse!

Some of you may have read about our farming practices, and noted that we have been trying to regulate our pest problems in both our vegetable and ornamental greenhouses with biologic pesticides and the introduction of parasitic and predator insects.  Our motivation for this type of insect control are a couple of reasons. It is environmentally safer and cleaner for growers and end users. The downsides are many, not the least of which is that it is a very expensive form of control. It is more complicated than just reading the label and spraying a pesticide for a pest. The product (good or “beneficial” bugs) do not have a shelf life as the bottle of pesticide does.  And when a problem arises, it can take six to thirteen days for the product to arrive after ordering it. You have to know the life cycle of the bad bugs as well as the beneficial insects. That makes things yet more complicated. (I wanted to be a farmer, not an entomologist…)

So it’s a big deal, it’s expensive and complicated. It is an art as much as a science. But we have been trying to do it this way for fifteen years. We have now developed an annual plan of prophylactic releases,  based upon when we open greenhouses, what plants go in them, the crops, and the historical problems that have cropped up and when that has occurred.   All this, knowing that at some point in the spring aphids, white flies and thrips  (the horticultural equivalent of President Bush”s “Axis of Evil”)  will show up. Hand in hand with the prophylactic release of beneficial insects there comes  a monitoring or “scouting” plan that weekly makes you systematically assess insect and disease problems by observing trends in insect populations. For example, you are never going to be totally”pest free” so by observing and counting pests weekly on a yellow sticky card that attracts the pests and understanding the swell and ebb of populations, you can make a pest control strategy. Sometime things run like a top, sometimes they go to hell in a hand bag. You can always tell when the latter happens because you can read the lines of frustration in Anne and Pooh’s faces. But when its working right,there are enough predators to keep the  populations of bad guys surpressed  but enough bad guys to support a healthy population of predators and beneficials. Its a balancing act. See? I told you it was tricky.

We didn’t come up with this kind of control on our own. We weren’t that smart. Some forward-thinking individuals from the Extension Services of our land-grant universities in Maine, Vermont and New Hampshire got together about 15 years ago and said “There has got to be a better way than hammering away at an insect pest problem with chemicals until the bug develops resistance and we have to find another chemical…besides I hear that Pooh Sprague hates spraying his greenhouses weekly…”  Well, maybe not the last part, but they were savvy enough to realize there might be a way of mimicking the way the natural insect populations are kept in check in an outdoor environment, and adapting that to a greenhouse environment.

So when you come to the greenhouses this year you will see little yellow cards again and you will know that we are monitoring pest populations with them. UVM is doing some experiments here, and you will be told that certain plants can’t be sold. And you will know that the tiny parasitic wasps we released at dusk on Tuesday are going about their business as you go about yours. And you can, we hope, appreciate the fact that we are trying to reduce our biologic footprint in our own corner of the world. 

March 11

The weather of late has been grim,with little sun,seasonably cold  temps and more snow  that in recent memory. Admittedly, it is such small potatoes  when one looks at the  suffering perpetrated by the recent  collection of natural disasters and wars.  Reminds  us of the saying  “I cried because I had no shoes,until I saw the man who had no feet..”  Nonetheless,the  weather is pretty crappy even while  we  are still  proceeding  as though  spring is going to come . At this time of year there are seeds to be sown, plants to be potted, tomatoes to be grafted and planted. There is  usually a last flurry of  educational and grower meetings  that occur as well before farmers get into their brisk  seasonal pace of activities. In our circle of grower friends, we get together for a potluck dinner in late March each year  that has come  to be called  “The Last Supper”, because it is the last time  so many of us can be found in a room together until after the killing frosts of fall.

Many of the recent meetings have been generating a lot of angst in the small grower community about the impending food safety regulations that will be implememented by the FDA. Many smaller growers feel that they are shouldering the burden imposed by the FDA  from a problem that was a result of large corporate agriculture. But the general consensus  among the small New England  growers is that it cant  be a bad thing to review how you wash and handle your produce and modify  your production practices to  further reduce what little risk there may be for the end user.  Mike, Ray and I attended a work shop put on by UVM that helped us look at and develop a simple food safety plan for our farm. Initially it is a pilot program for interested farmers but perhaps could be adopted regionally. There were a few very interesting  take home points for us. 1) the investment is stainless steel  sinks in which you might wash greens is important because it sanitizes the best of any surface.  2) a regular testing of wash water is a good practice to insure low levels of pathogens (something I never thought about much because its the same stuff I drink and brush my teeth with) 3) If you triple rinse lettuce,the dilution rate of pathogens is logarithmic. Wow. Not a dilution rate of 3 times. Thats pretty huge. So,thats s huge impact  and all for the cost of a used 3 bay sink. Thats the kind of change one can embrace. We see food safety as a work in progress,so we will annually review the farm plan and see how we are doing.

I have rattled on too long. Time to put the ice grips on the boots and venture out to the greenhouses…