OPINION
Mark Straver explains why it's never worth taking risks when choosing your planting list
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t only takes one infected plant or wood pallet for harmful pests and diseases to enter our country and cause damage to our landscape. The emerald ash borer, for example, has destroyed millions of ash trees in America, and would utterly devastate our native ash trees already struggling from ash dieback. Plant health regulations are constantly changing due to the effects of climate change, so it's something we always have to stay on top of. The oak processionary moth is a pest from Europe that damages oak trees and can harm humans if their hairs are touched or inhaled. We didn’t worry about this 20 years ago because our climate was too cold, but thanks to rising temperatures and an import of infected oak trees in 2006, it is now established in London and restrictions are in place to prevent further spread.
Importance of PLANT HEALTH
We work with plants every day and want to encourage everyone to be scrupulous when it comes to making responsible plant choices
There's nothing wrong with the odd nibble Natural predators keep pests in check but introduce a foreign species into an ecosystem and the existing wildlife doesn't know what to do with it. Birds take up to five years to learn if a new insect is safe to eat. Insects maintain the balance in our ecosystem, but habitat destruction, unsustainable farming, and pesticides have had an effect, and the
DISCUSSING PLANT HEALTH
latest State of Nature report shows our bugs are declining, with some species decreasing by 65% to 70%. At our nursery, we avoid pesticides wherever possible and use Integrated Pest
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Management. We bring in 'good insects' to deal with the 'bad insects' and allow a controlled number of pests to be present for the predators to feed from. Previously, the RHS deducted points for the smallest nibble on a plant in a show garden. But designers such as Cleve West and Tom Massey, along with Project Giving Back, have made significant efforts to actively campaign for better plant health, and the odd nibble is now perfectly acceptable. Defra and the Plant Health and Biosecurity Alliance Defra upholds strict measures, but we all share the same goal, and we appreciate the guidance we receive from chief plant health officer Professor Nicola Spence CBE and her team. We're proud to have a great relationship with Defra, which teaches plant health to its students at our nursery. Our team also sit in with Defra to ensure we stay informed, and we have a dedicated team member solely responsible for plant health. All staff are well-trained to identify pests and diseases. My business partner, Robin
Wallis, and I wrote our plant health policy together, which was used as a template by the Plant Health and Biosecurity Alliance, of which we are both members. Always play it safe and ask for advice We don't want to come across as 'preachy', but we work with plants every day and want to encourage everyone to be scrupulous when it comes to making responsible plant choices. By following the rules and playing it safe, you can help reduce the risk of pests and diseases. We use a traffic light system as a guide where plants are categorised by colour: red plants should not be imported, yellow plants require checking, and green plants are safe. If you're unsure, then ask for advice – there are always alternative plant options available that we can suggest for your projects.
MARK STR AVER Mark Straver is a thirdgeneration nurseryman based in Hampshire and has worked with plants since the age of 16. He is joint owner and director at Hortus Loci, which he founded with Robin Wallis in 2011. He’s known in the gardening world for his ability to source the best wholesale plants internationally, using his extensive knowledge, connections, and experience in the industry. hortusloci.co.uk
Pro Landscaper | November 2023 105