Plant Pest Control

Identify the pest before you treat

Most products here name the pests they are written for, so a wrong call wastes the bottle and the cycle. Spider mites stay under 1mm, feed on leaf undersides and can web over leaves and fruit; their eggs often need magnification. Fungus gnats, also sold against as scarid fly, are 2–5mm dark flies whose larvae live in the growing medium. Whitefly are 2–3mm and lay on leaf undersides.

Monitoring kit sits here next to the treatments: loupes and microscopes from 40x to 200x, a green LED torch for the dark period, and yellow sticky traps. The insect glue traps for pots are sold as the cheapest way to notice a first infestation, not as a control in their own right.

Our range of plant pest control

Contact sprays and leaf washes

A contact spray only works where the droplet lands, so coverage decides the result. PureCrop1 is a colloidal micelle built from corn and soybean oil, and its maker rates it for use up to the day of harvest. Green Cleaner works by dehydrating and suffocating soft-bodied pests. Ed Rosenthal's Zero Tolerance is a food-grade mix of cinnamon, clove, rosemary and thyme oils that evaporate instead of leaving residue. Sharp Shooter concentrates are natural pyrethrins from chrysanthemum flowers, and Mite-Rid uses neem, garlic and eucalyptus oils. Kill-A-Mite sits apart: a registered pesticide carrying 18g/L abamectin, used at 1mL per litre.

Fungus gnat and growing-media treatments

Flying adults are not how you beat gnats — the larvae in the medium are. CX Horticulture T-Drops are extremely concentrated (1mL treats 100 litres), and the maker states they will not affect beneficial micro-organisms. Gnat Nix is a top dressing that blocks adults emerging and deters females from laying. G-Natural is a granular biocide you water in.

Barriers, traps and lights

De-Nat is food-grade diatomaceous earth, sold as a foliage dust and as a granular for the substrate surface, working as an abrasive barrier. The IPM Anti-Bug LED and the Obri fly trap use light rather than chemistry. The fly trap puts a 365/395nm UV LED over a concealed glue card and is rated to about 120 square metres.

Systemic concentrates — check the label

A systemic is taken up by the plant and works from the inside. That buys weeks of protection and narrows where it can be used. Broad Blue Protect is stated at up to 8 weeks; Media Protect Granular at 6–8 weeks. Both labels say they are not for food crops or consumable plants. Smart Garden Stop Mite Pro is also a systemic; its maker states it suits edible crops when used as directed. Read the product page before you buy.

How to choose a pest control product

1. Identify first, treat second. Mites, gnats, thrips and whitefly are different jobs. A loupe is cheaper than treating the wrong pest.
2. Check whether the label covers edibles. Several products here are for ornamentals only and say so plainly. Do not assume one is safe on food crops because the one next to it is.
3. Match the treatment to where the pest lives. Leaf pests need a spray that reaches the undersides. Larvae in the medium need a drench, a granular or a top dressing.
4. Plan for the egg cycle. One spray rarely finishes it. Kill-A-Mite and Mite-Rid both instruct a repeat 3–4 days later so hatched eggs are hit before they lay; Zero Tolerance suggests three treatments two days apart for mites and thrips.

Safety and the label

Handling notes are not shared. The page runs from food-grade diatomaceous earth to a registered abamectin pesticide. Kill-A-Mite's copy recommends masks and gloves and says to observe withholding periods; PureCrop1's states protective gear is not required. Timing differs as well — Broad Blue, Zero Tolerance and Athena IPW all ask for high-intensity lights off, and Athena adds a room near 22°C and 3–4 hours drying. Follow the instructions on the product you bought, not a category page.

Yellowing or spots are often not a pest. The store's guide to yellow leaves and common grow problems covers the causes worth ruling out first, and the foliar spray range covers feeding through the leaf once the plant is clean.