Fusarium, alongside botrytis, is one of the most aggressive types of fungi for cannabis; it can destroy branches or even entire plants in no time at all. It’s so damaging that it was even used as a bio-weapon.
What is Fusarium?
Fusarium is a type of fungus that causes fusarium wilt, a common illness in various types of grow. Some of the most common species that attack cannabis plants are: Fusarium Oxysporum Sp., Vasinfectum and Fusarium Oxysporum Sp. Cannabis.
Fusarium grows in soil or substrate, although its spores travel through the air, water, on pets etc. Fusarium can stay in the soil over the winter, as well as other plants, and their spores can be transported up to 400km on the wind.
As we were saying earlier, Fusarium is an incredibly dangerous fungus for cannabis plants.
- It rots the roots, causing water-related signs of stress.
- It causes plants to lose strength and stop growing and flowering.
- It can dry up branches and even the entire plant.
- Plant leaves go yellow and fall off.
- It’s highly problematic in hydroponic grows, especially in those with a recycled watering system.
- Roots and branches affected by fusarium wilt can’t be cured, all you can do is prevent the illness from happening.
How to Identify Fusarium in Cannabis Plants
You’ll need to pay close attention in order to identify symptoms in your cannabis plants as soon as possible.
- The first symptom that indicates the presence of fusarium are leaves falling off, as if they needed water.
- After a few days, the branches will also begin to dry up. If it’s a small plant, you may confuse these symptoms with drought. In larger plants, if it happens on just one branch, it’s a clear sign of fusarium. The leaves on the affected branch will begin to die and fall off.
- There’s usually a brown stain at the base of the main stem. If you cut it, you’ll see that the inside is infected with a dark brown colour. This is a clear sign that your plants are ill.
How to Prevent Fusarium
Prevention is an absolute must when it comes to infections like fusarium wilt that can’t be cured.
- Keeping your growing area clean is super important; grow room, grow tent, balcony, greenhouse or garden.
- Get rid of any dead leaves on the ground; compost them in order to recycle them, do not place them in your substrate.
- Do not wear your street clothes into your grow. Wash your hands or wear gloves before touching your plants. After touching a plant, wash your hands or change gloves.
- Clean the flowerpots using water and detergent, and then with bleach before using them again. Do not leave dirty flowerpots near your plants.
- If you’ve had an insect or fungi infestation, do not reuse substrate. Even if you managed to get your plants to the end, do not reuse substrate for growing cannabis; use it for other plants if you wish, but it’s not worth potentially ruining your plants by saving some money on substrate.
- Anti-stress products such as Revive, Regulator, Alg-A-Mic or Supervit can help to increase your plants’ strength which makes them more resistant to issues such as fungi infestations.
As well as hygiene and stress-relief products, the best way to prevent fungal infections is by using Trichoderma. Keep reading and we’ll tell you all about the benefits of this bio-fungicide.
How to Get Rid of Fusarium
Plants that have Fusarium can’t be cured. If your plants are flowering and it’s only affecting one branch, you may be able to harvest the rest. If they get sick during the growth period, you’re better off starting again.
The best way to prevent fusarium is by using Trichoderma fungus, a beneficial type of fungi for your plants.
Trichoderma naturally grows on bark, decomposing wood and other places. It has an emerald green colour and a liquorice-like aroma. It can be found in products like Bio 16 Trifag, Aktrivator, Asir Fruit, Bactrex, Trikologic, Trikologic S, which also contains mycorrhizae, and Piranha. These are bio products that don’t have any sort of negative effect on your plants, and are non-toxic for people and animals.
We recommend applying various doses to make sure they’re present in your substrate. For example, once at the start of the grow, with every transplant, and 15 days after using chemical fungicides.
- Colonizes the substrate swiftly and fights with pathogens like Fusarium, Pythium, alternatia etc. for root space. It can even take them over.
- Produces secondary metabolites with antibiotic and fungo-toxic qualities like tirchodermina, gliotoxina, viridin etc.
- Stimulates root growth and improves nutrient absorption indirectly.
- Decomposes organic materials and stimulates substrate microbial life.
If you have any questions regarding Fusarium, at La Huerta Grow Shop we have a team of experts at the ready.