Because of the challenges we are currently facing at the farm, I’ve gone back to being involved at the most basic levels of our farm operations. Last week I walked each of our 135 plant houses and looked at every single plant.

The other day I wrote here that we are taking out all the virus-infected plants. But I have learned, through years of experience, that one must always challenge assumptions. So I asked Dr. Scot Nelson, a plant pathologist from the UH Hawai‘i at Manoa’s College of Tropical Agriculture and Human Resources, if he would come evaluate our virus problem.

The first thing he said was that the samples I’d submitted the other day tested negative for virus. I could not believe it. Everywhere I looked in the tomato houses I observed it. How could there be no virus?

I showed Scot what I thought were virus-infected plants and he took four samples, each slightly different in its stage of infection. Besides taking samples of what I thought were virus-infected plants, Scot took apart the growing media of an infected plant and evaluated the roots, which looked perfectly healthy. They were all white except that there were no roots where water sits in the bags holding the plants in the media.

He surmised that the roots were waterlogged and lacking oxygen, so the roots could not survive. I made a note to cut a drain hole in the bags.

Because of the lack of roots, he also left open the possibility that it might be a nutritional deficiency, caused by the roots’ inability to take up nutrients. He suggested we do a tissue analysis to check on the plants’ nutritional status. If the levels are low, he told me, we might have to compensate by spraying some fertilizer on the leaves.

I filed all this away.

This afternoon Scot called me. The three youngest samples tested negative for virus. But the oldest sample tested positive. Scot had told me that sometimes viruses cannot be detected in the youngest leaves that exhibit symptoms. So it appears we do indeed have a virus; just one that is difficult to detect in young tissue.

I’m writing all this down because it illustrates the truth that one needs to check, double check and question assumptions in order to be a plant doctor. One can never assume anything.

There’s a lot more to being a farmer nowadays than just sticking a plant in the ground and waiting.

Later this week, nutritional consultant Pete Bunn is flying in from O‘ahu for the day, and we’ll see what else we learn.