Greenhouses — An Organic and Nonorganic Grower Viewpoint

In response to a Voices piece posted on Friday, June 21, I would like to offer a different perspective into greenhouse farming vs. open field/orchard farming debate as someone who has long been involved in both practices.

I was 11 years old when my family immigrated to Carpinteria from Holland in 1967. Our farming roots date back to the 1700s, ranging from open field to orchards and eventually to greenhouse production. I currently own an 11-acre greenhouse and farm 50 acres of certified organic avocados, with 15 more soon to be certified organic as well. In other words, I am intimately familiar with both types of farming and recognize the advantages that each comprise.

There is no doubt that my avocado orchards are more pleasing to look at than my greenhouses, but let’s not judge a book by its cover. Before I built my greenhouses in the 1980s, I grew gypsophila, also known as Baby’s Breath, in outdoor fields. This turned out to be both challenging to my bottom line and to the environment. I planted in July, fertilized it to make it grow, and sprayed it with pesticides to protect it from harmful insects. Often by the time my plants were ready to be harvested, inclement weather would destroy the plants that I had been tending for months. If the rains were severe, there was soil erosion that washed into the nearby creeks along with any residue of fertilizers and pesticides.

Then I switched to growing flowers in greenhouses. I found my crops were protected from adverse climate conditions. I had much higher yields, better quality flowers, a more efficient use of natural resources, and far lighter impacts on the environment. We grow our crops hydroponically. When done correctly, this can be arguably the most environmentally responsible method to grow delicate crops, whether they be flowers, lettuce, or cannabis. Hydroponic greenhouses don’t turn their soil into a sterile wasteland but preserve it beneath ground cloth to prevent weeds from growing. The rain that falls on my greenhouses is captured in a detention/recharge bio-basin where any potential pollutants are filtered out by plants before the water is recharged to the groundwater basin.

Our closed-loop hydroponic fertilizer injection system ensures that every drop of water and fertilizer is recycled and that there is zero irrigation runoff. This ensures that nitrates and other fertilizers are kept out of our creeks, streams, and groundwater. Sure, greenhouse production can use more energy than open field farming, but it uses far less energy and water per plant than irrigating fields with inevitable runoff. In my experience, it is the most efficient and cleanest way to grow certain specialty crops at scale.

When it comes to cleaning up Santa Barbara County’s environment, greenhouse cannabis growers are leading the way. Without a doubt, the switchover from cut flowers to cannabis has dramatically reduced pesticide use in the county. Unlike any other crop, the standards for cannabis are nearly zero tolerance for dozens of pesticides and chemicals known to cause human health issues. A cannabis crop would have to be destroyed if it tests higher than 4 parts per billion on 68 different pesticides, or for E. coli, molds, and other substances deemed a health risk. Every conventional pesticide’s active ingredient is tested so consumers are protected from ingesting or inhaling harmful chemicals. No other agricultural crop is tested to these standards.

I have found that the most effective way to control damaging pests in cannabis with little to no chemicals is with beneficial insects that prey on pests. It’s more expensive than pesticides, but it’s cleaner. Some cannabis growers supplement these beneficial insects with organically certified chemicals such as soap and highly concentrated solutions of cloves. It should be noted that health authorities deem these natural pesticides as benign to humans, or they would be on the state’s banned list of chemicals. Who would have guessed that cannabis growers would emerge as the leaders in the cleanest and most cutting-edge pest control methods in horticulture? Yet that’s what’s happened.

And it’s also what instigated this much hyped conflict between cannabis growers and conventional avocado growers. Some of the large-scale avocado growers cling to a practice of spraying potent synthetic pesticides from helicopters, which can drift with the wind into nearby ranches and neighborhoods. A popular one is Agri-Mek, which the U.S. Environmental Protection Agency warns is toxic to bees, birds, fish, mammals, and humans. So cannabis growers asked these avocado farmers to please advise them when the helicopters are coming, so they can close their greenhouse vents and not get doused with toxic pesticide. No one told them not to spray these chemicals, even though I don’t like it drifting into my organic avocado orchards or posing a lethal threat to bees from my 50 hives that pollinate the trees in my organic orchards and neighboring nonorganic ones, too. Their response to our concerns about pesticide drift and our requests to be notified of their helicopter spraying? They blame the cannabis growers for exposing the fact that helicopter spraying cannot be done without drift, a practice that they have been doing for decades without consequence.

Of course, the emerging cannabis industry has struggled with odors, but CARP Growers (Cannabis Association for Responsible Producers) is hard at work to mitigate the harmless terpene odors emitted by the cannabis plants with vapor-based equipment using essential oils and carbon filtration. The odor annoyance has vastly improved as more growers are installing the odor mitigation systems. As the county rolls out permits and shuts down greenhouses that are out of compliance, the odor nuisance should become a nonissue.

For some of our neighbors, it cannot happen fast enough. Fair enough. They have struggled with the skunk-like smell and claim health impacts — even though there’s no credible scientific evidence to support such claims. I wish they would redirect a tiny portion of their passionate concerns to read the EPA’s write up of Agri-Mek, the toxic pesticide used by some of their neighboring avocado farmers. And to those farmers I would urge them to consider joining the ranks of us organic growers. Not only do we receive higher prices per pound for our certified organic fruit, we sleep better at night knowing that we are not exposing wildlife and our families and friends and neighbors to nasty, toxic chemicals.