Biosecurity and plant passports
Biosecurity in the garden and beyond, the site factors that raise the risk, how climate change adds to it, and the role of plant passports and phytosanitary certificates.
Key points
Summary
| Area | Key facts |
|---|---|
| Site factors (5.1) | Visitors, neighbouring land, water courses and irrigation, imported plants, soil, mulch and timber |
| Garden level (5.2) | Quarantine, inspection, reputable UK-grown stock, clean tools and boots, safe disposal, no plants from abroad |
| Regional level (5.2) | Movement controls; demarcated zones around outbreaks |
| National level (5.2) | Border inspections; plant passports; phytosanitary certificates |
| Climate change (5.3) | Faster pest breeding; new pests survive milder winters; stressed plants less resistant |
| Legislation (5.4) | Plant passports: traceability within the UK trade. Phytosanitary certificates: imports into Great Britain |
Some serious threats, such as box tree caterpillar, arrived through the plant trade.
Test yourself
What is the main purpose of quarantining new plants?
- To let them adjust to the light levels on site
- To harden them off gradually before planting out
- To check for pests and diseases before they can spread
- To give them time to establish new roots in the pot
Which document is issued by the exporting country for plants imported into Great Britain?
- Plant passport
- Phytosanitary certificate
- Plant Breeders' Rights licence
- An RHS recommended label
Why does climate change increase biosecurity risk?
- Warmer summers kill off native predators of pests
- Wetter weather means more plants must be imported
- Milder winters let new pests survive and establish
- Higher CO₂ makes plants more attractive to pests
Video transcript
Biosecurity means stopping pests and pathogens from arriving and spreading. This lesson covers biosecurity at garden, regional and national level, how a changing climate increases the risks, and the laws behind plant passports.
In the garden, quarantine new plants for a few weeks, and inspect them before planting out. Buy from reputable suppliers, ideally UK-grown. Clean tools, boots and pots between sites. Dispose of diseased material safely, not on the compost heap. And don't bring plants back from holidays abroad.
The risk depends on the site. Public gardens receive many visitors, whose boots and vehicles carry soil. Neighbouring woodland, farms and gardens can be sources of infection. Rivers and shared irrigation water can carry water-borne pathogens, such as Phytophthora. And sites that import plants, soil, mulch or timber face the greatest risk of new threats.
Biosecurity works at three levels. In the garden, it's quarantine, hygiene and inspection. At regional level, outbreaks can be contained with movement controls, such as demarcated zones around an infected site. And at national level, border checks, plant passports and phytosanitary certificates stop threats entering the country.
A changing climate increases the risk. Warmer conditions let pests breed faster, and milder winters let pests from warmer countries survive and establish here. At the same time, plants stressed by drought or waterlogging are less able to resist attack. So biosecurity matters more than ever.
Plant health legislation protects the country. A plant passport is an official label that travels with plants moved between professional operators in the UK. It makes plants traceable, so an outbreak can be tracked back to its source. A phytosanitary certificate is issued by the exporting country for plants imported into Great Britain, confirming they have been inspected, and are free from listed pests and diseases.
One exam tip. For a purpose question, say what it does, and why that matters. For example: plant passports record where a plant was grown, and how it has moved. That's the point. So if a pest or disease is found, it can be traced to its source, and the outbreak contained. That's the development.
This is one of 33 lessons in Unit 1
The full course adds sorting drills, flashcards, a written question with a model answer, and a printable sheet for every lesson.