The Best Garden Pests
In an ideal world pests and beneficial organisms live hand in hand together, you need one to feed the other ideally the beneficial ones to eat the pests, however it doesn’t always work that way no matter how balanced your garden is. At home i have never had to use any form of pest killer, this doesn’t include my hands, boots, tissue, washing up liquid oh and chop sticks. The chop sticks were brilliant for picking up Chafer Grubs, just in case you were wondering if i had lost the plot.
Don’t get mixed up with the good pests and the bad ones. I’m only going to go through the most popular ones I’ve encountered and possibly one or two you wish i hadn’t mentioned.
There are so many books on Pests and Diseases in the garden choosing the right one is difficult. I use mostly “How to get rid of garden pests and diseases” by Andrew Mikolajski. Its useful in helping to diagnose your plants problem not just for pests but for physiological reasons also. I’ve quickly gone through this book and made some notes on all the pests i want to tell you about, whilst doing so I came across some of the coolest names for pests. Horehound Bug, Squash Bug, Spring Tails, Lesser Bulb Fly, Nail Gall Mite, Bag Shelter Moth and Plague Thrips, luckily for us most of these are found in Australia and America and they can stay there, the pictures are pretty gross. We do have some very gross pests of our own here in the UK though.
In no particular order: (There are many chemical options for removing these pests to find the best one ask at a good garden center, I am only giving organic options).
Wanted: The Greenfly
Size – 3mm
Colour – Green
Damage – They are sap suckers so will leaves become curled and distorted, growth is then slowed and production of fruit is reduced.
Plants affected – Vast range of plants including all your runner beans, cucurbits eg cucumbers, and your ornamental plants especially grandmas roses.
Control – Spray with washing up liquid, and or rub off with hands or become friendly with the tit family, blue and coal tits are the most likely, also any ladybirds you know.
For more information visit RHS Website on Greenfly.
Wanted: The Glasshouse Whitefly
Size – 2mm
Colour – White
Damage – The nymphs excrete honeydew which encourages sooty mould.
Plants affected – Potentially all plants that are grown under glass including houseplants.
Control – At college we used the parasitic wasp Encarsia formosa and also insecticide soap. Do not use the parasitic wasp when using chemicals.
For more information visit RHS Website on WhiteFly.
Wanted: The Lily Beetle
Size – 7mm
Colour – Red
Damage – If your unfortunate to have lots of these beetles they can munch their way through your lily and fritillaries in a day if your really unlucky. They are the nemesis of lily growers. We have to go on lily beetle patrol every day to stop these little red devils.
Plants affected – Any lily and fritillaries.
Control – Pick and squish the little blighters off the leave, watch out they like to jump and play dead.
For more information visit RHS Website on Lily Beetles.
Wanted: Carrot Fly
Size – 5mm
Colour – Maggots are orange/white, the flies are black.
Damage – The maggots tunnel into the roots (edible orange carrot) turning them brown and effecting their flavour. If serious enough the carrot can rot in the ground or where stored.
Plants affected – Mainly carrots, but they can also go for celery, parsley and parsnips.
Control – Try not to bruise the leaves when thinning out as the smell attracts the females to lay their eggs, also a barrier of clear polythene all the way around the carrot plot at least 60cm high to help exclude the low flying females. If you have a large vegetable plot practice crop rotation so that the larvae isn’t in the soil over winter ready to eat the carrots you plant in the same plot. Its not proven to help that much in small vegetable plots, but couldn’t hurt.
For more information visit RHS Website on Carrot Fly.
Wanted: The Vine Weevil
Size – 9mm
Colour – Black with creamy yellow specks on their bodies.
Damage – The adults lay their eggs in the soil around host plants, white grubs appear then they munch their way through roots, killing the plant from the bottom up. The adults attack from the top by eating the leaves, all in all not very nice creatures.
Plants affected – Most plants that are grown in containers, also soft fruits, Cyclamen and Fuchsias.
Control – Find a parasitic nematode to control the larvae and try to catch and squish the adults, like you would the Lily Beetle. If your container plant looks like its not doing very well, its going yellow, leaves are falling off, etc then check its roots and see if you can see any grubs, if you find some or even the adults then check all pots, and eliminate them rather than just looking at the immediate pots. Remember they eat roots, if the roots of a plant have disappeared but there is no sign of vine weevil its too late, so check all your pots to catch them before they eat their way through the next one.
For more information visit RHS Website on Vine Weevil.
Size – 4mm
Colour – Pale pink, yellow or grey oval creatures that can easily be mistaken for a woolly fluffy fungi.
Damage – These sap sucking creatures drain plants, leaving leaves distorted and growth stunned. The honey dew created from mealybugs attracts sooty mould. This is the woolly effect your likely to see.
Plants affected – Because they like warm, moist conditions most plants under glass, including house plants can be effected. They mainly go for succulents including cacti, ferns and palms.
Control – A biological control Cryptolaemus montrouzieri, a type of ladybird, provides some control. Any badly effected plants should be discarded. To help avoid them remove dead leaves and prunings.
For more information visit RHS Website on Mealybugs.
Wanted: Chafer Grubs
Size – 2cm
Colour – Very ugly fat white grubs with brown heads. Don’t get them mixed up with Cockshafer grubs and vine weevil grubs.
Damage – They eat the roots of grass causing the grass to turn yellow and then die. In worst cases entire lawns can be desecrated. This is what happened to my parents front lawn, Dad was devastated by the sheer damage they caused and what they
Plants affected – Grass!
Control – A pathogenic nematode Heterorhabditis megidis can provide some control, only apply this in summer, unfortunately this is usually when you don’t realise you have a problem, it isn’t until late autumn you see that the grass is very patchy if not all dead. When you lift up the soil all you have is the top grass no roots, very easy to remove, unfortunately the grubs bury themselves deep especially in winter so catching them before this is critical. We dug over every inch of the lawn to pick as many as we could. Chop sticks were very useful. We managed to half fill a large bucket with them. Not very pleasant! We just have to hope that that and the nematode wash was enough to stop them.
For more information visit RHS Website on Chafer Grubs.
Check out my post on why not all slugs and snails are bad coming soon!