Whitefly Control Without Pesticides

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In the last 14 years, Water Fresh Farm co-owner Jeff Barton says he’s had no significant pest problems in his half-acre of greenhouse vegetables – and beneficial insects are the only protection against whitefly, thrips and spider mites in the Hopkinton, Mass. operation. It may not be for everyone, but we asked Jeff to describe the benefits of his unique pest control program and how it works.

Q: How long have you had a biocontrols program with your vegetable crops?

Barton: We have been growing since 1997. We only grow vegetables. We started out just with tomatoes and now we have expanded to grow beefsteak tomatoes, cucumbers, Boston or Bibb lettuce, sweet Italian basil, baby spinach, herbs and we’ve just started growing microgreens. We decided soon after we started that we wanted to grow hydroponically and without pesticides.

The first year we learned what that really meant. We got a whitefly infestation and it had a huge impact on our crops. The following year we worked with Dr. Merle Jensen and started an Integrated Pest Management (IPM) program. Since then, we have only used beneficial insects to control pests. We bring in Encarsia formosa [parasitic wasps] to control whitefly in our tomatoes. We do it prophylactically. We get cardboard strips from Biobest that have the Encarsia formosa eggs on them, and we hang them on the tomato plants. We use them throughout the year and it’s worked out well. We still get some whitefly in the greenhouse but we’ve been able to manage it effectively without needing anything else.

For cucumbers, thrips and spider mites are an issue, so we bring in predators for those as well – they come in little bags and we distribute that on plants in the growing area throughout the greenhouse.

Last year, my grower started bringing in banker plants that will attract the pests. The pests will be on those plants and it gives the beneficial insects more food.

Q: Why did you decide to go with just biocontrols?

Barton: It was our personal preference and also the program made sense from a marketing aspect. It works, and people understand it. They “get” ladybugs. They understand there are predatory bugs that go after pests. They intuitively understood the value of that.

Q: How much whitefly control do you get with the beneficials?

Barton: I don’t know if I can get as specific as a percentage, but we’ve been able to manage it very effectively. The pests will still get into the greenhouse, but we have been utilizing the beneficial insects prophylactically, so they’re in the greenhouse before we have a problem. They have been able to manage the pest so in our view, there is no impact on the plant health, and therefore, no impact on crop production.

Q. Was it difficult to learn how to use them?

Barton: No, not really. We worked with Biobest and they have been great. They’ve come on site a few different times to understand what we’re trying to do and design a program for us to help manage any kind of whitefly that might come into the house for the size of the crop we have. Rather than us trying to become the expert and design it all ourselves, we got help from Dr. Jensen and from the manufacturer to help us understand what we should be doing.

And it’s not super expensive. The return on investment is hard to determine, because you’re using it as a preventative. If we didn’t spend the money, what would have happened? By introducing it are we getting more production? I don’t know.

But I can tell you in our first year in the greenhouse we did get whitefly and it was amazing how rapidly it went from “Hey, we have a little bit of a problem” to an absolute infestation. It really wasn’t much time at all. We have been able to manage it pretty effectively just with beneficial insects for the last 14 years.

Q. How is the beneficials program a part of your marketing effort?

Barton: We have our own market, so we sell a lot of our product here, but we also do a big wholesale operation for the tomatoes and cucumbers. We’re in the higher-end grocery stores around here now, including Whole Foods, Roche Brothers, and a handful of Stop & Shops. It’s a great story with those customers.

The market we built connects directly into the greenhouse. I do a talk on Saturdays in which I explain what we’re doing and the beneficial insects are always an important part of that. Invariably people say, “It’s a bug war!” They get it. We let the bugs battle it out but the good side always wins, and it protects the plants.

Richard Jones is the group editor for Greenhouse Grower and Today's Garden Center magazines.

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3 comments on “Whitefly Control Without Pesticides

  1. Ronald Valentin

    Hello Richard, Jeff and Barney, Thanks for this great article and explaining how bio-control really can do an amazing job. Key is to start early and I can truly say that the staff at Water Fresh Farms has done an amazing job for year already in getting the Encarsia, Eretmocerus in the greenhouse in time to get them established. Ronald Valentin Biological Control Specialist Technical Trainer and Coordinator Biobest USA Inc

  2. Pamela Bloom

    Great to hear you have success. Is there a link to connect to Biobest? We have tried introducing bio controls on a limited basis but without an enclosed house and a year long growing cycle in south Florida I have doubts the systems will prevail for long.