We are all well aware that insects can cause some nasty plant diseases, and we also know that humidity and water imbalances can result in disastrous fungal problems— especially in a hydroponic environment. However, there is another cause of deadly plant disease circling your greenhouse like a shark and infiltrating your precious crop, and it goes by the name abiotic.
Look abiotic up in a dictionary and you will find descriptions like, “not of a biological nature”, or “inanimate and non-living.” A slightly more useful definition might be: an abiotic disease is caused by non-living influences like heat or humidity.
These diseases are also referred to as physiological disorders and can be a little tricky to diagnose. Since they’re a direct result of non-living influences, we need to turn our attention to our environments to detect the cause of an abiotic disease.
Influences on abiotic disease
Common influences resulting in abiotic disease in your greenhouse include:
- Poor air circulation
- Heat and humidity
- Extreme light sources
- Nutrient deficiencies or toxicities
- External air pollutant infiltration
- Contaminated tools or equipment
- pH imbalance
- Heavily compacted growing media
- Contaminated or broken air filters
Nutrient deficiencies are one of the biggest causes of abiotic disease. Next on the list of most common would be pollutants entering the growing environment, then high humidity levels and environmental factors—sun, wind, heavy rain and even wildlife fall under the flag of environmental influences that regularly contaminate traditional outdoor farms.
Luckily, those of us growing hydroponically or in protected indoor gardens are one step ahead where environmental factors are concerned. We might need to keep an eye on issues like external temperatures—which can affect our indoor environment—and be aware of which bugs have infiltrated our local area (in case they try to slip through the cracks), but unless we knock over a reservoir and cause our own indoor flood, we’re generally pretty safe from most environmental factors like animals and torrential rainfall.
Visually identifying abiotic symptoms is where things become difficult. If you have a pest infestation, you can generally see the invader and figure out pretty quickly what you need to do to rectify the situation. The problem with visually identifying an abiotic disease is that the symptoms are very similar to those caused by pests or fungal and biological diseases.
Abiotic disease prevention
As the old saying goes, prevention is always better than a cure when it comes to disease, so follow these tips to avoid an abiotic outbreak:
- Keep your growing environment clean
- Remove any dead or dying foliage
- Check air vents and circulation measures
- Avoid heavily compacted media
- If you use tools that have been used outside, sterilize them
- Keep on top of nutrient strengths, pH levels and EC levels
- Consider introducing an immunity building additive that will build resistance to plant disease
- Stay on top of humidity levels and avoid excessive moisture build-up
- Monitor your light and heat sources
- Keep an eye on external temperatures and its effect on internal temperature
- Take note of insects invading your local area
As you can see, there are many factors to take into consideration when assessing and testing your equipment and environment.
An abiotic disease will destroy your plant's physiological system, weaken your crop's immune system and make it susceptible to other nasty elements lurking in your greenhouse. Know what a super healthy variety of your chosen crop looks like and learn exactly what it is that causes stress to your plants if you want to avoid a disease of the abiotic kind.