Protect your greenhouse from ethylene and carbon monoxide

Each new greenhouse season Michigan State University educators and specialists hear of ethylene and carbon monoxide problems in greenhouses somewhere in the Midwest. This article is devoted to understanding the symptoms of ethylene damage on plants and the human symptoms of carbon monoxide poisoning both due to faulty greenhouse heating symptoms.

 

Floriculture and vegetable crops grown in greenhouses that utilize natural gas or propane fueled heaters can be susceptible to ethylene injury according to MSU Extension. Ethylene (C₂H₄) is an odorless, colorless gas that acts as a plant hormone. Plants are very susceptible to ethylene injury at levels from 0.01 to 1 ppm or more. No other air pollutant causes a greater range of symptoms than ethylene gas. Symptoms range from shedding or shattering of flower petals, misshapen or malformed leaves and flowers, thickened stems, leaf yellowing or chlorosis, stunted plant growth, flower bud and leaf abortion to epinasty or twisting.

 

The effects on greenhouse crops will vary with the plant species and growth stage, temperature, length of exposure and the concentration of the ethylene. I have noted plant injury symptoms more often in plastic greenhouses compared to glass greenhouses due to the airtight nature of poly-greenhouses.

 

To learn more about ethylene and carbon monoxide, and to view an annual heating unit checklist, click here.