Lewis Creek Farm
Notes About Specific Crops

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1) In cabbage family crops (broccoli, cauliflower, cabbage, Brussels sprouts etc.) we use B.t. (Bacillus thuringiensis), an organic spray, for the control of Cabbage Worms.

2) Potatoes: The biggest problem is with Colorado Potato Beetles, Entrust, an organic spray, to control them. However, usually once a year one application of a synthetic pyrethroid is needed to control Potato Leaf Hoppers.

Late Blight (of the Irish Potato Famine fame) can be very destructive. When it hits the whole field will melt away to nothing in just a few days. Rainy cool summers can make it particulary bad. We had 3 or 4 years back in 2013-2016 when we had to spray for it. We haven't had to spray for it in the last few years. This is a classic case of IPM: "Don't spray if you don't have to." We watch the Potato field and the forecast. Frequently we an get away without spraying for Late Blight at all. When we have had to spray for Late Blight, we have been applying 2 sprays: Ridomil Gold and Tanos. They are very expensive, but are much less toxic than most organic sprays.

Most conventional potatoes get 6 to 12 sprays not approved for organic production. Our potatoes only get 1, or perhaps in a late blight year, 2 such sprays.

3) Eggplant is the absolute favorite food of Colorado Potato Beetles and the plants are very sensitive to their damage. For this reason it is occasionally necessary to use something stronger than B.t. like a synthetic pyrethroid for their control.

4) Zucchini, Summer Squash and Cucumbers: The early plantings (harvested through August 15th) usually manage with 1or 2 applications of Kaolin Clay "Surround" (organic) But occasionally they require 1 or 2 applications of a synthetic pyrethroid to control the striped cucumber beetles. This is never applied with fruit present, and is never applied to late plantings (Harvested after August 15th).

5) Tomatoes are now No Spray. We used to have to make several applications of cupric hydroxide (organic spray) to help control leaf diseases. Now we just keep them dry in an unheated greenhouse.

6) Carrots routinely get a herbicide spray of Linuron to control weeds. This is applied at least 2 months before the start of harvest.
Our carrots get only 1 herbicide spray. Most conventional carrots receive 4 to 6 sprays that are not approved for organic production.

7) Our Strawberries are sprayed 1 time with Malathion to control Tarnished Plant Bugs (TPB). The plants get sprayed just as the first blossoms start to open. The fruit themselves never get sprayed at all.
The TPB attacks the blossoms and cause the fruit to develop poorly. Fruit from damaged blossoms are small, have a hard knob at the point, and a bitter taste. The plants get sprayed just as the first blossoms are opening, so that there are no TPB around during the bloom period.

8) We now grow our Sweet Corn entirely without pesticides.
We transplant it all and that allows us to use no herbicides.
To control European Corn Borers (worms in the corn) we bring in tiny parasitic wasps (Trichogramma ostriniae) which lay their eggs in the worms' eggs, so the worms never develop.

9) The Onions get no sprays at all.
We used to spray them for weeds, but now we plant them through balck plastic and we don't have to spray them at all.

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