Slugs and snails are land molluscs (class Gastropoda) that feed with a rasping tongue, the radula. The grey field slug (Deroceras reticulatum) is one of the most widespread plant-feeding species. They feed at night or in wet weather and hide under mulch, boards and pots by day.
In practice
Damage is ragged holes, chewed seedlings and shredded low leaves, plus shiny dried slime trails. They matter most for direct-sown outdoor seedlings and fresh transplants; established cannabis outgrows them. A night check with a torch after rain confirms the cause. Practical controls are removing hiding places, drip irrigation instead of evening overhead watering, copper or abrasive barriers around beds, beer traps and hand-collection. Iron phosphate baits are a widely used low-toxicity active ingredient; check what is registered locally. They occasionally hitch into greenhouses on pots set on the ground.
Don't confuse with
- Cutworms: chew stems through at the soil line; no slime.
- Caterpillars: leave frass pellets instead of slime.
- Damping-off: rotted, pinched stems, no feeding marks.
A seedling is a young cannabis plant from emergence of the cotyledons until it has several sets of true leaves, typically the first 2-3 weeks.Transplanting moves a plant and its root ball into a new container or the ground; done gently it causes little shock, but GenetixBay advises against it for autoflowers.Drip irrigation delivers water or nutrient solution through tubing and emitters directly to each plant's medium, in measured amounts on a timer or controller.Copper (Cu) is a micronutrient used in photosynthetic electron transport and lignin formation; plants need only traces, and excess is toxic to roots.Phosphate is the ionic form in which plants absorb phosphorus, mainly H2PO4- at the normal root-zone pH of 5.5-6.5.Moth caterpillars of the family Noctuidae, such as the black cutworm (Agrotis ipsilon), that hide in soil by day and chew through seedling stems at night.The collapse of seedlings or cuttings when soil-borne pathogens such as Pythium, Rhizoctonia solani and Fusarium rot the stem at the soil line.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.Systematic, regular inspection of plants, traps and roots to detect pests and disease early, identify them correctly and record numbers for decisions.
