Damn flies!

[aes]

Hey folks,

I have planted loads of potatoes in bags in the back garden (about 8 bags with 4 tubes in each) and they are all next to each other forming a cluster, for wants of better terms. The thing is, I have noticed, lots of little black flies at the bottom of the stems near the soil just floating about in the air. They are tiny tiny but still enough to annoy me! Is there a way to get rid of them!? Are they doing any damage?! The leaves down there look a bit munched on to be honest.

Any thoughts?

Thanks for your help - again!

[Alice]

Are the potatoes planted in compost AES. ? Are these flies coming out of the compost ? If they are then they are little nuisance pests but don't do any damage that I know of.

Someone on here said sprinkling chilli powder on the surface of the compost got rid of them but I haven't tried it.

[ginger ninger]

I can't for the life of me think what they are called, but they lay there tiny eggs in the soil, when they hatch you'll have tiny maggot like grubs. I once grew indoor mushrooms and they were full of them, took me forever to get rid of the little blighters.... Someone will be along to advise you on how to get rid of them.....Good Luck

[aes]

Alice, they are in compost, some organic veg sackks, I'm not sure what brand. I might try the chilli thing!!

[21again]

I can't for the life of me think what they are called, but they lay there tiny eggs in the soil, when they hatch you'll have tiny maggot like grubs. I once grew indoor mushrooms and they were full of them, took me forever to get rid of the little blighters.... Someone will be along to advise you on how to get rid of them.....Good Luck

I think they are called Fungus Gnats.

[snohare]

If it is fungus gnats, they don't do much direct harm but can pass on diseases. They like damp soil, adding vermicullite or sand to the top reduces their numbers, and so does flypaper. (Until it gets utterly covered with corpses !)
I'm sure there is a sticky in Growing Techniques about how to trap them using almond oil - I have found they drown themselves in pots of water, just not at a high enough rate...

[ginger ninger]

I think they are called Fungus Gnats.

Thanks.. i just called them infuriating little buggers

[leoblackcat]

I read somewhere that you can get rid of the the little grubs in the soil by pouring a solution of water and hydrogen peroxide on the soil. It won't kill the plants as it basically just oxygen and water - not sure whether it is ok on potatoes though?...

[snohare]

I'd guess that hydrogen peroxide is so quick to break down that it wouldn't get into the potatoes, Leo. That's why it is so good as rocket fuel ! (Mark you, just a guess, so if you get explosive wind aes....)

[Two_Sheds]

Fungus gnats are encouraged by over-watering. Their maggots will eat plant roots, so they aren't a good thing to have.

[snohare]

Thank you Two Sheds, very informative resource there, I've bookmarked that.
I am on a real learning curve with these this year, once I had them on my windowsills their numbers went up to the hundreds ...back down now to a couple dozen I'm happy to say !