General gardening topics

Phormium mealybug pest and how to treat it

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Phormium mealybug is a pest that originates from New Zealand but is able to thrive in the UK outside, even in the winter which is unusual as all other types of mealybugs usually occur in greenhouses as they need a warm temperature but not the phormium mealybug.

Most mealybugs are a problem because they remove the sap from your plant which can affect their growth rate and then they excrete excess sugar onto the plant when they leave, which is called honeydew. The Honeydew lands on the leaves and the stems and gets colonized by sooty mould which turns the surface of your leaves black. The Mealybugs themselves are like small pale woodlice but you usually notice the fluffy white wax you notice first.

Mealybug can be very damaging especially on young plants but older established plants can usually live with the problem often unnoticed.

The insects usually cluster at the base of leaves and then cause heavy infestation which depletes your plant vigour and cause the foliage to die off prematurely. If you have an older, more established plant it might be somewhat more tolerant and survive without a lot of damage as already mentioned.

How to try and control mealybug

It can be very difficult to control these insects because they get concealed at the base of leaves or at the margin where different leaves fold together. This can make it difficult to reach them if you do spray a pesticide over the tops of the leaves. Unfortunately, there are very few products that give you as a home gardener any level of control but there is a product called Provado bug killer that is a systemic insecticide which means it’s taken into the plant’s system and poisons the mealybug when they suck the sap from the plant.

Provado 30 ml Ultimate Bug Killer Concentrate
  • Makes up to 60 litres.
  • Fast acting formula.
  • Contact insecticide that protects for up to 4 weeks.
  • Kills most common insect pests on an extensive range of ornamental plants.

Prevention is key

  • The best steps are preventative. Make sure that you examine your phormium carefully before you purchase it, and avoid any plants that show even the slightest sign of a mealybug infestation.
  • If you have plants that are very established, they might tolerate a light infestation and survive just fine so you won’t have to do much.
  • If you have a heavily infested plant particularly a younger plant it might be best to simply replace them. You can something divide a plant and plant a section which does not have mealybug.

Last update on 2021-12-28 / Affiliate links / Images from Amazon Product Advertising API

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