If you grow cannabis at home, you’ll eventually ask “what is the best way to prevent powdery mildew when growing cannabis indoors at home?” When you grow cannabis, you will certainly encounter and deal with cannabis pests and diseases, including infamous powdery mildew. Killing it is one thing, preventing is another. Ben Franklin was right: “an ounce of prevention is worth a pound of cure”
Powdery mildew occurrences are a common and troublesome challenge for home-growers, especially if you live in an area prone to powdery mildew. You can also develop issues if you grow in an overly humid environment like a basement. Geographic locations like New Orleans, Louisiana (which has the highest average relative humidity percentage among large US cities) or Jacksonville, Florida can be some of the worst for mildew infections.
Prevention is Key
There is no silver bullet, but there are many preventative practices to follow in your indoor home grow to avoid powdery mildew problems. As a home grower, preventing powdery mildew must be a crucial component of your strategy, whether you’re growing in a grow room or grow tent. If you ignore preventive care, it’s practically guaranteed you’ll wind up with powdery mildew infestations on your plants, ultimately ruining your crop. At which point, all you can do is work on stopping powdery mildew, since it wasn’t prevented
Nevertheless, powdery mildew is such a pervasive airborne pathogen, that even when you practice preventive measures you can still end up with powdery mildew in your home grow. Don’t be disappointed, you won’t be alone. Commercial cannabis and home growers have been fighting and dealing with powdery mildew in cannabis cultivation throughout all of time. Keep calm — there is help for this challenge. Down below you’ll learn about harnessing the power of NASA-developed technology to take your preventive measures to another level.
Catch it Quickly
Home growers do need to be on guard or suffer the consequences, and no one wants to lose a harvest. To be on guard, you need to get in the habit of inspecting your plants’ leaves regularly, even daily, for any signs of powdery mildew. The very beginning signs of powdery mildew might start out as a speck the size of a watch battery. If you see several leaves with much larger patches of powdery mildew, it’s likely you have not been paying attention over the past few days. Try to catch it as early as possible. Remove infected leaves and put them in a plastic bag and zip it up to bring out of your grow space.
Don’t forget, it doesn’t take long for powdery mildew to spread and completely coat cannabis plants to the point of no return.
Powdery mildew can be a problem in the vegetative and bloom phases of growing cannabis, as well as during the drying phase. Although treating powdery mildew episodes during the vegetative phase is easier than the bloom phase or harvest phase, nothing beats prevention. Prevention trumps treatment!
One last reminder before sharing some best practices in powdery mildew prevention. Don’t ever smoke or otherwise consume cannabis with powdery mildew!
Prevention is the home growers best strategy to deal with powdery mildew. Here’s a list of the best preventive practices to keep your home grow free from powdery mildew as best as you can.
Tried and True Best Practices For Powdery Mildew Prevention
Keep unnecessary people and pets out of your home grow.
It makes no sense to allow people or pets to walk through your home grow space unnecessarily. It only increases the odds of exposure to powdery mildew. An infestation can easily come in on people’s clothing and shoes, and it can also hitch a ride on pets. Many grow tents and grow rooms have see-through windows for this reason. The goal is to limit the touch-points of people as much as possible. It may sound strict, but it’s crucial to maintaining cleanliness (and not just to prevent powdery mildew, but other pests and diseases too.)
Even if you are growing cannabis strains that are known to be resistant to powdery mildew, this recommendation can spare you from much future trouble and is a fantastic habit to form from the beginning.
Control humidity in your home grow.
One of the best ways to prevent powdery mildew from harming your home grown cannabis is by dialing in your humidity percentages. In veg, keep your humidity levels around 70%, and in bloom and harvest, the humidity goals are 55% – 60%. Since powdery mildew thrives in high humidity, you can ensure successful powdery mildew prevention by following these humidity guidelines. Use air conditioning, dehumidifiers and oscillating fans to dial in your ideal humidity levels. Opening a window can help lower the humidity, but on the other hand, it can also bring in more airborne spores of powdery mildew. If you have a sealed grow room, and you have an air intake system, be sure to use an intake HEPA filter to prevent contaminants like powdery mildew from entering your growing space. And, of course, always use an Airoclean 420 home / hobby unit to keep the air contaminant-free.
Clean/Disinfect new plants brought into your home grow.
Always disinfect any new teen plants or clones introduced to your grow room or grow tent. No exceptions! If they are small enough, you can dunk them in a bucket with one of cleaners listed below. Or you can spray them completely — the tops of leaves, under the leaves, and on the branches — spray til run-off. There are several organic products to use like Plant Therapy, Green Cleaner, Trifecta, or Zero Tolerance.
Regularly apply foliage sprays in your home grow.
All home growers need a regime of foliar sprays to help prevent powdery mildew. You can use the above mentioned products like Plant Therapy, Green Cleaner, Trifecta, Horticultural oil, or Zero Tolerance. Rotating these products is the best way to approach your application strategy. Don’t rely on just one.
One of the best products to prevent powdery mildew is called Serenade. Serenade is a contact fungicide. The main ingredient in Serenade is Bacillus subtilis strain QST 713. To use it, you’ll thoroughly coat your plants to run-off, covering tops and bottoms of leaves to ensure efficacy.
You can also make your own safe homemade foliar sprays using items like household hydrogen peroxide or isopropyl alcohol. There are many dilution ratios of hydrogen peroxide (3% H2O2) and isopropyl alcohol (91%) to try and test since different cannabis varieties will respond differently. The worst case scenario is that you may cause “leaf burn”. Test the solution on just 1 or 2 leaves before applying thoroughly.
Always start with a “least to most” approach and don’t apply the hydrogen peroxide and alcohol solutions directly. For example, you can start off testing 1 part alcohol / 3 parts water or 1 part hydrogen peroxide / 2 parts water. Don’t spray when the plants are under grow lights as this can increase the likelihood of leaf burn.
One bonus of using household isopropyl alcohol and hydrogen peroxide is they also function as insecticides/pesticides.
Clean your grow room or grow tent after each grow cycle or episode of powdery mildew.
As a best practice, always rigorously clean your grow room and grow tent if you are experiencing powdery mildew in your grow. You should also clean it after each harvest or every 3 months. Most growers use a bleach/water solution or straight household hydrogen peroxide (DO NOT ever mix these two chemicals). Spray and wipe every nook and cranny, every bar, and carefully wipe your fans and the exteriors of your light fixtures. (Only wipe the metal or plastic surfaces — do not wipe light bulbs.)
Upgrade Your Powdery Mildew Prevention with NASA-Developed Technology
Level up with the AiroClean420 Home / Hobby Air Purification System in your home grow.
By using an Air Purification unit, home growers can leverage cutting-edge proprietary technology used in commercial cannabis cultivation in their personal home grow. Most home growers don’t think about air purification, but commercial cannabis farms certainly do. It’s time for home growers to catch up and reap the benefits of modern science for year-round indoor cannabis growing right at home.
The AiroClean420 Hobby Home Unit is the best air purifier on the market. It can literally decimate, destroy, and kill powdery mildew spores through a process using Photocatalytic PCO technology. It is the best method you can use to prevent powdery mildew.
In conclusion, although you may have troublesome issues with powdery mildew in your home grow, there are solutions. Implementing an AiroClean420 Hobby Home unit, maintaining proper humidity levels, and practicing rigorous foliar sprays offer home growers impressive results. And don’t forget to keep the neighbors, friends, and critters out of your home grow space.