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Simple one. I removed my sunflowers from the pot today as they were showing a rust leaf problem and not doing great. They did flower and got pretty tall but then just went sick and I tried the nutrition etc. I am in the Sydney region Australia.

So when removing them from the pot I found some of the grubs in the pictures below, sorry a little out of focus but they are about 0.75cm long and getting a shot on a cell phone with macro mode is like finding a honest politician.

Smile for the camera....

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There were several of them in the pot. Now I know not all insects and other critters are nasty to my plants but should I ready the flame throwers or just ignore them?

From my research this afternoon they appear to be curl grubs according to this page

Since I am concerned that they have spread to other pots(Veggies, herbs etc) what type of pesticide could I use to rid myself of them while keeping the safe for consumption?

Namphibian
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  • I'm not sure these are actually cockchafer grubs, because they're usually white or pale grey, and the ones in your pic are obviously pretty black or dark. Unable, as yet, to come up with an alternative ID though... – Bamboo Feb 09 '17 at 12:51
  • I suspect they're African Black Beetle larvae rather than cockchafer, but the neem treatment you link to should work https://goo.gl/images/MJ9Toi - most damage caused by these is by the beetles eating roots and growing tips – Bamboo Feb 09 '17 at 13:00
  • @Bamboo yeah they dont quite fit the normal cockchafer(horrible name) pics. Seems like they only infested one pot which is a relief. Since the sunflowers are ruined I pulled then as I use the pot for some basil seedling. I also let then turned the pots out and since today was a whopping 44 degrees in my area it got pretty hot and most died. Will check in the morning for survivors as since they eat root and if they are small in number they might be useful against any roots that need to be removed. – Namphibian Feb 10 '17 at 11:29
  • ooh, I wouldn't let any survive, frankly - some inevitably will that you just haven't found, but definitely dispose of any you do find. Roots you don't want you can remove more efficiently yourself anyway – Bamboo Feb 10 '17 at 12:58
  • @Bamboo no survivors after yesterdays 47 degrees heatwave, today was 44 and tomorrow is a nice balmy 38. The sun is the ultimate pest control. Jokes aside I left the pot soil spread out on the ground over the last two days in a rather large plastic container just to see how they would handle the heat. Still getting the neem oil but it is 20:30 pm and 30.8 currently I just cant apply anything in this heat. – Namphibian Feb 11 '17 at 09:24
  • Nature's pesticide, that hot sun! It's freezing here in the UK... – Bamboo Feb 11 '17 at 11:17
  • @Bamboo it ain't hot it's scorching some of my seedling trays warped in the heat. It's unbelievably hot here I had to pull over on freeway today to wipe sweat out of eyes, and I had the aircon full blast. I have done the hottest day in history in Hong Kong two or so years ago but this was crazy hottest summer ever in Australia. It's really unreal, looking on the bright side of life for a moment I must admit I never defrosted chicken so fast without a microwave and the pans and pots tend to get ready quickly, would not mind a bit of cold though like 10 degrees which will put us at 30-34 range. – Namphibian Feb 11 '17 at 13:31
  • Oh it's 00:32 and 26 degrees right now... Good weather but not for this time of the morning. – Namphibian Feb 11 '17 at 13:33
  • I'm assuming you mean 47degC - yes, roasting, I know Oz has been having increasingly serious problems with heat, this year so far being the worst. Sadly, its only going to get worse - its likely caused by climate change, which has random effects in different places, of course. I also know of someone who moved back to Norfolk in the UK after 35 years in Oz to get away from the heat that's become so unbearable, so yea, I believe you.... – Bamboo Feb 11 '17 at 13:41

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These look to me like Cockchafer larvae. they eat a lot!

They thrive here in your pot because they found perfect breathing and rich humus for them. They are harmful to many veggies you can grow in your yard, and can even harm small plants and bushes, because they eat the roots sometimes.

You don't need pesticide to get rid of them, though. They are easy to collect by hand when you return the earth in the spring, because of their big size and usually limited number. Just put them on a plate (on a table, away from nasty little cats) for their natural enemies to see them and feast: the birds will be delighted.

J. Chomel
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  • Except the plants are in pots, so treatment is likely necessary as a soil drench of some kind - or all the pots turned out,grubs removed, pots cleaned and sterilized, and filled with new potting soil. – Bamboo Feb 08 '17 at 18:28
  • In Sydney, Australia? – Stephie Feb 08 '17 at 21:23
  • @Stephie correct, Toongabbie area Sydney Australia to be a little more precise. – Namphibian Feb 08 '17 at 23:23
  • @Bamboo, as long as the plants don't die, its not necessary to remove every last one of the beasts. They will live, eat, grow, and go away. I would just remove the one visible when changing pots. I don't think sterilizing would do anything, since new Cockchafer will come flying by and start reproduce again. Better attract natural enemies. – J. Chomel Feb 09 '17 at 07:25