Cultural control means using growing practices to make the crop a poor home for pests and disease. It covers the environment, plant spacing, watering, media, crop timing and cultivar choice. It is the foundation layer of IPM and usually the least expensive.
In practice
Examples on cannabis: keeping humidity and dew point in check late in flower to deny Botrytis; moving air through and under the canopy against powdery mildew; letting the top of the medium dry between waterings to cut fungus gnats; cool, oxygenated nutrient solution against Pythium; spacing plants and thinning crowded interior growth; avoiding overhead watering outdoors; and choosing cultivars with known tolerance, such as those carrying mapped mildew resistance. Removing weeds and host plants near outdoor grows reduces insects that carry viruses. None of these act fast, but together they lower pressure so other tools work.
Don't confuse with
- Biological control: living natural enemies, not growing practices.
- Sanitation: hygiene; overlaps, but focuses on cleaning rather than how plants are grown.
- Chemical control: pesticides and fungicides, the last layer.
Plant density is the number of plants per unit of canopy area; more plants raise yield per area up to a point but shorten veg and reduce uniformity.Integrated pest management: preventing and controlling pests by combining monitoring, prevention, cultural, biological and, as a last resort, chemical tools against set action thresholds.Dew point is the temperature at which air becomes saturated and water starts condensing; when leaves or buds cool to it, free water forms and mould risk jumps.Botrytis cinerea, the fungus behind bud rot or grey mould, which rots dense colas from the inside in cool, humid conditions late in flower.A fungal disease, on cannabis caused mainly by Golovinomyces ambrosiae, that grows as white powdery patches on leaves and buds and thrives in moderate humidity.Small dark flies of the genus Bradysia (family Sciaridae) whose larvae live in wet growing media, feeding on fungi, organic matter and young roots.A genus of oomycete water moulds, such as Pythium myriotylum and P. aphanidermatum, that cause brown, slimy root rot, especially in warm hydroponic systems.Using living natural enemies, such as predators, parasitoids, nematodes and microbes, to suppress pests and diseases instead of, or before, chemical sprays.Cleaning and disinfecting rooms, tools, containers, irrigation and people's clothing so that pests and pathogens are not carried from plant to plant or crop to crop.
