- What are Cultural Controls?
- Genetic Diversity
- Irrigation Practices
- Air Temperature & Relative Humidity
- Wind Conditions
- Identify Pests & Pathogens
- Identify Nutrient Stresses
What Are Cultural Controls?
Cultural controls in Integrated Pest Management (IPM) is the manipulation of abiotic and biotic conditions to control the agroecosystem with the goal of making the environment unsuitable for pest populations. Abiotic conditions include genetic selection, genetic diversity, irrigation practices, fertilizer use, temperature, relative humidity, wind, and light.
It is important to grow a variety of cannabis genetics to ensure production does not suffer along with providing a selection of products to consumers. Separating cannabis strains into their own sections in a flower room is important not only for harvest, but also for limiting the spread of pests and pathogens across the room which can allow growers to focus on hotspots. Certain strains of cannabis can be more prone to cannabis pests or pathogens than other strains which leads a lot of growers to select resistant variety strains to help keep pest populations low and pathogens out of the garden. For example, Northern Lights is a popular strain that is famous for its relatively high yield potential and strong pathogen resistance qualities.
Proper irrigation practices are important for plant health and vigor. Without proper irrigation practices and a sound nutrient schedule, your cannabis plants will grow slower and inadequately for a robust production schedule. If you are overwatering or underwatering you can stress your cannabis plant too much and eventually the plant will die. For example, cannabis grown in coco coir and peat moss do well being watered every 1-2 days. If the coco coir or peat moss is taking more than 3 days to dry out, then give your plants less water for the next feeding and then readjust the amount of water given as the plant grows bigger. Plants grown in coco coir tend to drink more than plants grown in peat moss and soil which is why coco coir is usually more forgiving for overwatering than peat moss and soil. Plants grown in peat moss like to be nearly dried out between waterings while coco coir prefers a small amount of moisture inside at all times. Overwatering can asphyxiate the root system of the plant stunting growth and eventually killing the plant if left unchecked. Very wet substrates can be hotbeds for pest populations such as fungus gnats and pathogen spores which can sap the plant of nutrients causing nutrient deficiencies and the death of the plant. Another sign of overwatering is algae on the top layer of coco coir which also attracts fungus gnats. If you notice these symptoms, then let the medium dry out, flush the medium with water, then feed with nutrients when the medium becomes nearly dry again. If you have a fungus gnat infestation then it is recommended that you drench or chemigate the roots with a biopesticide such as azadirachtin or neem oil.
Air Temperature & Relative Humidity
Cannabis generally prefers higher levels of air temperature and relative humidity in its younger stages of growth and lower levels during its later stages of growth. Clones and seedlings prefer a range of 60-70% relative humidity and 75-80°F in air temperature. During the vegetative stage, cannabis plants prefer a relative humidity range of 40-70% and temperatures between 72-80°F while cannabis plants in the flowering stage prefer 30-50% relative humidity and 70-78°F air temperature. If you can easily control the air temperature and relative humidity, then the last two weeks of flower should have a lower air temperature and relative humidity for an increase in flavor and flower appearance.
Air movement is important in an indoor grow room because it can reduce the spreading of pathogens and pests, provide a consistent air temperature and relative humidity throughout the room, and strengthen plant stems and stalks. Cannabis plants should be provided with airflow above the canopy typically with oscillating fans and below the canopy with floor fans or you can utilize industrial ceiling fans to fulfill this goal. Avoid pointing fans directly at the plant canopy from short distances as it can cause wind burn.
Many pest and pathogen issues can reoccur after a harvest if cannabis plants are moved in without a thorough cleaning. Plant debris, dust, and dirt should all be wiped away then a proper cleaning agent should be applied to floor, wall, and utility surfaces. Grow lights, trays, stakes, scissors, plant containers, water pumps, and feed lines should all be thoroughly cleaned as well as any other grow equipment that was used during the last grow cycle.
Identify Pests & Pathogens
The identification of pathogens, pests and their damage are important to combat issues early and to combat them correctly using methods to contain and eradicate any problems before they take over large sections of a grow room. For example, two-spotted spider mites can be spotted as little white mites that live on the underside of cannabis leaves. Their damage includes stippling on the topside of cannabis leaves. Western flower thrips are tiny flying insects and they cause hash marks on the topside of cannabis leaves from their rasping-sucking mouthparts.
Identify Nutrient Stresses
Managing your nutrient schedule properly is important to foster healthy growth. Nutrient stresses include nutrient deficiencies and toxicities. The yellowing of lower, old growth could be a sign of nitrogen deficiency while dark green top growth with leaves clawing could be a sign of a nutrient toxicity. If nutrient stresses can be accurately detected, then the nutrient schedule can be adjusted and plants can grow healthier with less issues throughout its life cycle.
Ultimately, practicing proper cultural controls for indoor cannabis cultivation is key to limiting pest populations and the spread of pathogens which will help reduce your overall pesticide use while maintaining a healthy indoor cultivation grow space. Cultural control practices are a series of preventative measures. It is important to try and anticipate potential pest and pathogen issues before they occur to minimize their impact on plants.