Cannabis Damping Off: How To Spot And Prevent It From Happening

Cannabis Damping Off: How To Spot And Prevent It From Happening
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Cannabis Damping Off: How To Spot And Prevent It From Happening

If you are a cannabis grower, you may have encountered a problem called damping off. This is a fungal disease that affects cannabis seedlings and can cause them to die before they even have a chance to grow. In this blog post, we will explain what damping off is, how to recognize it, how to save your cannabis plants if they are affected, and how to prevent it from happening in the first place.

What is Damping Off in Cannabis Seedlings?

Damping off is a term that refers to the rotting of the stem and root tissues of cannabis seedlings. It is caused by various types of fungi that thrive in moist and warm conditions. These fungi can infect the seeds before they germinate, or the seedlings after they sprout. The most common culprits are Pythium, Rhizoctonia, Fusarium, and Phytophthora.

Cannabis damping off can occur at any stage of the seedling’s development, but it is more likely to happen when the plants are young and vulnerable. The fungi can enter the plant through wounds or cracks in the seed coat or the stem, or through the soil. Once inside, they feed on the plant’s tissues and cause them to decay and collapse.

What Are The Damping Off Symptoms in Cannabis?

Cannabis Seedlings damping off
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Cannabis Damping Off: How To Spot And Prevent It From Happening

The symptoms of cannabis damping off may vary depending on the type and severity of the infection, but some common signs include:

  • Degeneration of the leaves and stem closest to the base of the plant.
  • Discoloration of lower leaves and stem, usually yellow or brownish.
  • Small white spots on the stem at the soil line.
  • Wilting and drooping of the leaves.
  • Stunted growth and reduced vigor.
  • Collapse of the stem and death of the plant.

How Do You Treat Damping Off on Cannabis?

If you spot any signs of damping off you need to act fast and hope for the best. Unfortunately, damping off is often fatal and hard to cure once it has taken hold. The fungus that causes damping off can spread quickly and infect other plants in the same environment.

Therefore, you should remove any affected seedlings and treat the remaining ones with hydrogen peroxide. Hydrogen peroxide is a disinfectant that can kill the fungus and prevent further infection. You only need a small amount of 3% peroxide, about 1ml or 20 drops, to apply to the soil around the base of the seedlings.

For older plants that show symptoms of damping off, such as brown or black lesions on the stem or roots, you have a better chance of saving them. You should cut off any infected parts of the plant and apply hydrogen peroxide to the wounds to prevent further spread of the fungus.

How to Prevent Damping Off From Happening?

Cannabis Damping Off: How To Spot And Prevent It From Happening

The best way to avoid damping off is to prevent it from happening in the first place. Here are some tips on how to avoid this problem:

1. Don’t Overwater

One of the main causes is attributable to excessive watering. Excess moisture creates an ideal environment for fungal growth and infection. Therefore, you should water your cannabis seedlings only when they need it, and not more than once a day. Check the soil for moisture by inserting your finger into the soil about an inch deep. If it feels dry, water lightly until it is moist but not soggy. If it feels wet, wait until it dries out before watering again.

2. Improve Drainage

Another way to prevent it from happening is to ensure proper drainage of the soil. Use pots or containers that have holes at the bottom to allow excess water to drain out. You can also place a layer of gravel or perlite at the bottom of the pots to improve drainage. Avoid using saucers or trays that collect water under the pots, as this can create stagnant water that encourages fungal growth.

3. Control Humidity and Temperature

Humidity and temperature are also important factors that affect damping off. High humidity and low temperature create favorable conditions for fungi, while low humidity and high temperature inhibit them. Therefore, you should keep your cannabis seedlings in a controlled environment where the humidity remains around 40-50% and the temperature stays within the 70-85°F (21-29°C) range. You can use a hygrometer and a thermometer to measure these parameters and adjust them accordingly with fans, heaters, humidifiers, or dehumidifiers.

4. Don’t Cover Seeds and Seedlings

A lot of people think that seeds need to be covered with soil or plastic when they are germinating. This is not true, and it can actually cause problems for your seeds. Covering them creates too much humidity, which they don’t need. The only exception is when you are propagating plants from cuttings. In that case, you can use a humidity dome, but you have to change the air inside every day to prevent mold.

The best way to germinate seeds is to put them on top of wet soil or paper towels and keep them in a warm and dark place until they sprout. Then, you should move them to a bright and airy spot as soon as possible. This will make them grow faster and healthier, and avoid diseases like damping off.

5. Use A Sterile Growing Medium for Germination

Another way to prevent it is to use a sterile growing medium for germination. This means using soil or other substrates that are free of any pathogens or contaminants that could infect your seeds or seedlings. You can either buy sterile soil from a reputable source or sterilize your own soil by baking it in the oven at 180°F (82°C) for 30 minutes. You can also use other sterile mediums such as rock wool, coco coir, peat moss, or vermiculite.

6. Use Clean Pots and Clean Growing Utensils

It is also important to use clean pots and clean growing utensils when germinating and growing your seedlings. This means washing and disinfecting your pots, trays, scissors, knives, tweezers, and any other tools you use with hot water and soap, or a mild bleach solution. This will help eliminate any traces of fungi or bacteria that could cause damping off.

7. Do Nou Use Fertilizer and Teas on Seedlings and Check Your PH

Another common mistake that can lead to damping off is using fertilizers and teas during the seedling stage. Cannabis seedlings do not need any extra nutrients during their first weeks of life, as they have enough stored in their seeds. Adding fertilizers or teas can cause nutrient burn, salt buildup, and pH imbalance, which can stress the plants and make them more susceptible to fungal infection. Therefore, you should avoid using any fertilizers until they have developed at least three sets of true leaves.

You should also check the pH of your soil and water regularly, and adjust it if necessary. The optimal pH range for cannabis is between 6.0 and 7.0 for soil, and between 5.5 and 6.5 for hydroponics. If the pH is too high or too low, it can affect the availability of nutrients and the health of the plants. You can use a pH meter or pH strips to measure the pH and use pH up or pH down solutions to correct it.

8. Use Organic Antifungals or Biological Control

If you want to prevent damping off naturally, you can use organic antifungals or biological control agents that can inhibit fungal growth and protect your seedlings. Some examples of organic antifungals are cinnamon, chamomile tea, garlic extract, neem oil, or hydrogen peroxide. You can sprinkle them on the soil surface or spray them on the seedlings before or after germination.

Some examples of biological control agents are beneficial bacteria or fungi that can colonize the roots of your seedlings and compete with the pathogens that cause damping off. You can buy them as commercial products or make your own compost tea.

Also Important Is The Use of Quality Seeds from Quality Seed Banks

Cannabis Damping Off: How To Spot And Prevent It From Happening

One last thing to consider when germinating and growing cannabis seedlings is the quality of the seeds you use. The quality of the seeds determines the quality of the harvests, so you should always choose high-quality seeds from reputable sources. High-quality seeds are more likely to germinate successfully, grow vigorously, resist diseases and pests, and produce potent buds.

You can find high-quality cannabis seeds from our affiliates, all trusted seed banks that offer a wide range of strains and varieties to suit your preferences and needs. Whether you are looking for feminized seeds, autoflowering seeds, regular seeds, CBD seeds, or THC seeds, you can find them here with discreet shipping and guaranteed delivery.

Preventing It from Happening Is The Best Remedy You Can Adopt

Damping off can be a frustrating issue for cannabis growers, as it can cause your seedlings to die before they even have a chance to thrive. Fortunately, there are some simple steps you can take to avoid this problem and ensure a healthy start for your marijuana plants.

We hope this blog post was informative and helpful for you. If you want to learn more about damping off or any other aspect of cannabis cultivation, feel free to reach out to us. We are always happy to answer your questions and share our expertise with you!

Enjoy your growing!

FAQs about cannabis damping off

Some of the fungicides that can be used to treat seeds or soil are captan, thiram, metalaxyl, mefenoxam, fludioxonil, and iprodione. However, the effectiveness of these fungicides may vary depending on the type of fungus involved and the environmental conditions. Therefore, it is advisable to test the fungicide on a small batch of seeds before applying it to the whole lot.

Alternatively, biological control agents such as Trichoderma, Bacillus, or Streptomyces can be used to suppress damping-off fungi. These agents are naturally occurring microorganisms that colonize the seed or root surface and compete with or inhibit the pathogenic fungi. Biological control agents are generally safer and more environmentally friendly than chemical fungicides, but they may also have variable efficacy depending on the situation.

Unfortunately, damping off cannot be reversed once it affects the seedlings. However, it can be prevented by using sterile soil, avoiding overwatering, and providing good air circulation. However, once the disease has infected the seedlings, there is no cure. The best option is to remove and dispose of the affected plants and start over with new seeds or clones.


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