Grower Talk: Managing Pests Before They Arrive
Welcome to the first entry in a new series here on Redheaded Blackbelt, Grower Talk. Cannabis growers are invited to submit informative articles talking about issues and concerns unique to their culture and industry.
Below, an anonymous grower talks pest management.
Last year my garden suffered from one of the most devastating pests known to cannabis farmers: hemp russet mites. I managed to reap a meager harvest and over the winter months I spent at the library researching this pest in particular and pest management in general. I hope to apply what I have learned and hopefully my harvest will reward me for my diligence. Meanwhile, I would like to share a few tips that I picked up so that you will not have to endure the suffering that I went through this past year.
First of all, Integrated Pest Management (IPM) is a method of controlling pests before they get out of control. The founding principle is that the better you are at detecting and preventing problems early on, the less you will need to rely on pesticides later in the season. The first step in pest prevention is starting with healthy, pest-free, disease resistant plants. I know how easy it is to pick up a few trays of spider-mite infested OG clones from your neighbor but I beg you not to do it. These plants will require pesticides from the moment you bring them home. Perhaps the use of pesticides doesn’t bother you but consider their cost and the time it takes to apply them, all season. Growing from seed, buying clones from a trusted source of clean and strong genetics and/or growing strains that are pest and disease resistant are the best way for you to prevent pest problems later in the season.
The second step of IPM is monitoring. You can monitor the presence of pests in your greenhouse by setting out sticky traps, both the yellow cards that hang and sticky tape that you can wrap around plant stems or pots. Check these sticky devices regularly and record what you find. Are you seeing an increase or decrease in a particular kind of pest? Are there areas of your greenhouse where you are detecting more of this pest than in other regions? You would be wise to also invest in a microscope that magnifies up to 120x. You can use this microscope to investigate sticky cards or you can select plant material to inspect. This might sound like overkill but Russet mites and broad mites are both microscopic in size. The only way to detect them early is by inspecting samples through a microscope.
The third step of IPM is called “Cultural practices.” This includes keeping your greenhouse tidy, dry and well ventilated. Over watering and over fertilizing attract pests such as fungus gnats and aphids. Also, if you notice a problem, remove the specimen as soon as possible. I know how tempting it can be to hold on to plants with the hopes that they will become healthy again but part of keeping your plants clean and healthy includes isolating those plants that can and will infect all of the rest of your plants. As far as greenhouses go, cleanliness is a virtue.
The fourth step is bolstering the immune system of your plants. Think about the human body. If a person eats a diet that is rich in vitamins and minerals, they drink lots of water and breath fresh air, they are much less likely to get sick. Their immune system is robust enough to fight off disease. The same goes for your plants. If they are healthy and have a strong immune system, they are less susceptible to pests and disease. In addition to a balanced feeding regimen, kelp, nettles, spirulina, mullein and horse tail are all rich in minerals which help plants sustain their health through stressful situations such as during transplanting and transitioning into flowering. Keeping your plants well ventilated and appropriately watered also helps plants stay healthy and strong.
Over the course of the season, if you notice a problem arising, first try a mild and organic solution. In my reading about russet and broad mites, early applications of sulfur were the most highly recommended solution. Essential oil sprays, pyrethrum and neem oil can all be very effective if used early on. The problem with using synthetic pesticides, aside from the harm they cause our bodies and the planet, is that pests will develop a resistance to them. If you catch pests early you should be able to manage your problem with a minimal amount of organic solutions.
Finally I want to mention inter-planting. Not all plants are ideal to mix in with your medicinal garden. Last year I mixed in tomatoes, peppers, cucumbers and zucchini. However, when I realized that I had a pest problem it occurred to me that the plants that I had interplanted were both harboring pests and potentially attracting them. I deeply regretted mixing my vegetable and medicine garden as I ripped out my tomatoes. This year I plan on inter-planting my garden again but with plants that are known pest detergents such as garlic, marigolds and pyrethrum daisies. I will plant my fruits and vegetables in their own beds where I will not be as concerned about the presence of pests.
I hope this summary of what I learned this winter will help you think about your own pest management plan. The key is to be ready, with information and organic solutions, for when the pests arrive. For most of us the question is not whether or not they are coming it is a question of when and how we chose to manage them. Good luck out there!
for more information on IPM please see Statewide Integrated Pest Management Program: