More than just waterlogged

The rains in California between July 1, 2022 and April 13, 2023 have significantly impacted cannabis cultivators in the Golden State, and not just because of the amount of water they have brought.

When comparing the rain in this timeframe against its 30-year average (normal precipitation), it ranges anywhere from an increase of 74% in Northern California to 184% in Central California to 101% in parts of Southern California, according to the National Weather Service.

These rains, in some cases, were enough to put many cultivators out of business. Monterey County alone reports the highest canopy modification reductions over the past four years, along with 32 cannabis business closures from fiscal year ’22 to ’23. The poor, unprecedented weather has put these already struggling operators under even more pressure.

Let’s break this down and understand the impact on cultivation production and the people who manage it.

How does the rain impact the outdoor grower? 

1. Waterlogging: When there is excessive rainfall, the soil can become saturated with water, which can lead to reduced porosity and low air circulation in the soil. Waterlogging can also cause secondary issues such as restricting workers, vehicles, tractors, etc. to maneuver in and around the soil/site.

2. Soil erosion: Heavy rainfall can cause soil erosion, which is the loss of topsoil due to the high-volume movement of water. This can wash away valuable nutrients and organic matter, leaving the soil less fertile and less able to support plant growth.

3. Floods: Floods can wash away crops, damage irrigation systems and contaminate fields with debris and pollutants. The amount of runoff this year is expected to hit record highs with the potential for contaminated biomass being very high.

4. Delayed planting: Heavy rainfall can delay planting. This can lead to a shorter growing season (specifically a shorter vegetative season), which can reduce crop yields due to the lack of time adequately bulking the crop under long days before flower initiation in the fall.

Close-up of Red spider mites (Tetranychus urticae) on a injured hemp leaf (canabis sativa). It is a species of plant-feeding mite a pest of many plants.

5. Disease outbreaks: Excessive rainfall can create conditions that are favorable for the growth of plant diseases. Moisture and humidity can create a breeding ground for pests and diseases, which can devastate the crop from root and crown rots to mildew, molds and blights.

How does the rain impact growing when thinking about the greenhouse market? 

In many cases, excessive rains can impact greenhouse cultivation similarly to the field examples above. This year, thankfully, the rains mainly came in the late winter to early spring, before plants went in the ground. However, for greenhouse growers, that was a different story, as the clouds themselves caused an array of problems.

According to data on daily light integrals (DLIs) from the weather station at the StateHouse Cultivation greenhouse in Salinas, light levels dropped by about 40% compared to last year due to rains and cloud cover. The typical rule of thumb is that 1% more light equals 1% more yield.

While the StateHouse Cultivation farm was equipped to mitigate the problem, it could be devastating for many growers, especially those that don’t have adequate supplemental artificial lighting to compensate.

Increased Pests

Also, cultivators with less sophisticated systems could have been in a real bind due to the inability to keep the rain out and remove humidity and heat, which could cause plant stress and extreme disease outbreaks.

At StateHouse, we have seen higher than usual pest outbreaks after the rains, as if rainfall caused pests to migrate to dryer areas. Elsewhere across California, there have been reports of mass infestations of root aphids, thrips and fungus gnats in substrate from outdoor substrate inventory storage (pre-mixed peat, coir and wood-based palleted substrates).

In addition to pests, there have also been reports across the state of mass root disease and plant death due to plants sitting in water, irrigation schedules not being properly adjusted to meet reduced average temperatures and lighting.

When the light intensity decreases, plants undergo a series of physiological responses to adapt to the lower light levels. One such response is the closure of stomata. Under low light conditions, the energy produced by photosynthesis decreases, and the plant reduces its transpiration rate to conserve water. By not adjusting irrigation schedules, plants in potted conditions may also deal with waterlogging.

Helping employees

But even more important is the impact on workers and their families. The constant rains have made it difficult to get to the cultivation and production sites. At our facility we had multiple days where about 100 employees per day could not make it to the farm due to flooded roads or schools being out and workers having to stay home to care for their children.

And that’s on top of dealing with the property damage, displacements, infrastructure damage and cost increases on basic items like food that come with flooding.

Finally, excessive rainfall and its associated impacts can lead to increased stress, anxiety and depression, particularly for those who have experienced flooding or displacement. These mental health impacts can have long-lasting effects on individuals and families.

To address some of these challenges, we arranged for transportation for our employees who otherwise would not have been able to get to work due to road closures or difficult travel conditions. We also adjusted our cultivation schedule and techniques to reduce the number of cultivation staff needed on site.

Our human resources team also made sure that our employees had access to our employee assistance program, providing free confidential counseling services, financial advice and legal services. While these are difficult days for the industry as a whole and budgets are tight as a result, it is imperative that companies do what they can to support their workers through natural disasters.

It doesn’t just make good sense, it’s the right thing to do and it matters to our employees.