dreamgreen
- 62
- 18
When I first noticed them, I tried the simplest solution first: drench the soil with a 1:3 mix of 3% hydrogen peroxide and water to kill the eggs and larvae and allow it to get bone-dry before watering again, and also hang sticky strips to kill adults. The soil foamed up nice, and the sticky strips became coated with hundreds over the next few days—but by the time the soil was dry again, their numbers were even more than before.
So...i doubled the number of sticky strips to 4, hung them closer to the light, and drenched with the peroxide again. Again, a week passed and no real effect on their numbers, other than more dead gnats on the stickies.
Next step was to put some spiders in there...no shortage of them in my basement! I managed to get 6 in there and was happy to see webs in each of the four bottom corners the next day, with many dead gnats under the webs. Daily after that, more and more dead gnats in the corners and on the stickies, but again, no real dent in their overall numbers.
Sooo...frustration builds...next step was an insecticidal soap, sprayed directly on the leaves and soil, every day. I could see them die on contact. But again, 4 days of this and no change in overall gnat numbers. WTF?!?
This is when i added a 1” layer of fine sand on top of the dirt in each pot, after another peroxide drenching, and more soap spray. And lo and behold, their numbers started to decrease. Dare i hope...problem solved?
No. A week later the bastards were back in even greater numbers. And in addition, my two precious mother plants started getting some really funky twisted growth and thick stems, which i learned was likely due to root rot. Nasty smell at the drain holes confirmed it. The layer of fine sand was not letting the soil dry quickly enough. Plus the damned gnats were still getting to the wet soil to lay their eggs through the drain holes in the bottom of the pots.
What FINALLY worked was transplanting them into 2-gallon fabric pots (i used phat sacks), with the sand layer on top. That and a little Hydroguard took care of the gnats AND the root rot pretty quickly.
Literally thousands of dead gnats on the stickies and in the corners now, but only a few stray fliers! WOOHOO!
Hopefully my experience can help others entrenched in the gnat battle!
So...i doubled the number of sticky strips to 4, hung them closer to the light, and drenched with the peroxide again. Again, a week passed and no real effect on their numbers, other than more dead gnats on the stickies.
Next step was to put some spiders in there...no shortage of them in my basement! I managed to get 6 in there and was happy to see webs in each of the four bottom corners the next day, with many dead gnats under the webs. Daily after that, more and more dead gnats in the corners and on the stickies, but again, no real dent in their overall numbers.
Sooo...frustration builds...next step was an insecticidal soap, sprayed directly on the leaves and soil, every day. I could see them die on contact. But again, 4 days of this and no change in overall gnat numbers. WTF?!?
This is when i added a 1” layer of fine sand on top of the dirt in each pot, after another peroxide drenching, and more soap spray. And lo and behold, their numbers started to decrease. Dare i hope...problem solved?
No. A week later the bastards were back in even greater numbers. And in addition, my two precious mother plants started getting some really funky twisted growth and thick stems, which i learned was likely due to root rot. Nasty smell at the drain holes confirmed it. The layer of fine sand was not letting the soil dry quickly enough. Plus the damned gnats were still getting to the wet soil to lay their eggs through the drain holes in the bottom of the pots.
What FINALLY worked was transplanting them into 2-gallon fabric pots (i used phat sacks), with the sand layer on top. That and a little Hydroguard took care of the gnats AND the root rot pretty quickly.
Literally thousands of dead gnats on the stickies and in the corners now, but only a few stray fliers! WOOHOO!
Hopefully my experience can help others entrenched in the gnat battle!