Black flies swarming a planter box

Joined
Sep 24, 2022
Messages
7
Reaction score
0
Location
Stellenbosch
Country
South Africa
Hello everyone
In one of our large planter boxes there is thousands if little black flies. I am not sure what it is and how to eradicate it.
Any help would be appreciated
Photos attached
 

Attachments

  • image.jpg
    image.jpg
    349.7 KB · Views: 17
  • image.jpg
    image.jpg
    310.2 KB · Views: 17
Joined
Feb 13, 2021
Messages
3,433
Reaction score
2,146
Country
United Kingdom
Welcome to the forum.
I am the other end of the world and on another continent, so I am guessing a little. My guess is that they are some sort of midge or gnat, and the larva are living in the soil. You see them when they hatch out. If you water with one part 3% household peroxide (not the strong industrial stuff) to five parts water it should kill the larvae in the soil.
 
Joined
Sep 24, 2022
Messages
7
Reaction score
0
Location
Stellenbosch
Country
South Africa
Thank you very much for the reply.
I am quite desperate so will try that. Will it kill the plants? And will the soil be fine?
 
Joined
Apr 2, 2022
Messages
1,467
Reaction score
641
Location
Tennessee
Hardiness Zone
6b
Country
United States
Looks like a soldier fly but with a brown back. Maybe just immature?

I put my chicken poop in a pile and about summer time it is loaded with black soldier fly larvae. They compost the manure very quickly. Your soil must be rich in organic material.
 
Joined
Apr 2, 2022
Messages
1,467
Reaction score
641
Location
Tennessee
Hardiness Zone
6b
Country
United States
1 part 3% hydrogen peroxide, 5 parts water = 0.5% hydrogen peroxide. Shouldn't hurt your plant. I've soil drenched with higher strengths. I didn't know it would kill larvae though.
 
Joined
Feb 13, 2021
Messages
3,433
Reaction score
2,146
Country
United Kingdom
Peroxide is H2O2, it easily loses that extra atom of oxygen to make H2O, water, and adds the oxygen to something else, so no, adding an extra oxygen where it will stick is not going to be harmful to the soil, oxides are not poisonous, but if it is a living thing like a larvae ...
 
Joined
Apr 2, 2022
Messages
1,467
Reaction score
641
Location
Tennessee
Hardiness Zone
6b
Country
United States
I use it kill fungi and to aerate the soil. Waterlogged soil is one example to avoid root rot.

Higher strengths of hydrogen peroxide can kill your plant but I've actually soil drenched with straight 3% hydrogen peroxide before. It did seem to stunt the plant but not kill it. The plant eventually started to grow again and produce but it was noticably behind the other plants right next to it that didn't get drenched.

I don't know if it kills bacteria or not at those strengths. If it does, and if you think about it, bateria is what converts organic nitrogen into plant usuable nitrogen so would the transformation happen? Maybe that is what stunted the plant... I killed the bacteria so then nitrogen wasn't usuable for a while? Maybe the hydrogen peroxide oxidized the plant usuable nitrates into a non usuable form?
 
Joined
Feb 2, 2014
Messages
11,480
Reaction score
5,586
Location
La Porte Texas
Hardiness Zone
8b
Country
United States
I just now have seen this old thread and no one has answered it. These bugs name is Plecia nearctica aka Love Bugs. They are harmless to plants but can be an EXTREME NUISANCE. When they mate they do mate it is in huge swarms, sometimes so thick that it clogs up the radiator of an automobile resulting in overheating. I had no idea they were in South Africa though.

 

Meadowlark

No N-P-K Required
Joined
Feb 5, 2019
Messages
2,686
Reaction score
2,233
Location
East Texas
Hardiness Zone
old zone 8b/new zone 9a
Country
United States
Yep, that's love bugs alright. Good call Chuck.

The good news is they are harmless to plants, but the bad news is they can overpopulate to the extent to be a real pest. We have a spring and a fall explosion of them every year with fall seeming to be the worst. They make a real mess of vehicles that have to plow through them on the highways. Good for car wash business.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Members online

Forum statistics

Threads
26,734
Messages
257,883
Members
13,313
Latest member
PlntFnNan

Latest Threads

Top