This is my process, and it takes a bit more effort and time, but
no gnats. When used in an assembly line manner, it goes
faster than one would expect.

For this year's seeds I put used potting soil from pots that have been outside all season, along with some new potting soil, so the possibility of having gnats and their eggs was risky, I'm guessing. I needed to use the old stuff to have enough soil, and avoid having to make a trip out to buy more. I don't usually use old soil, but it
worked out okay.

Filled the pots with the soil, then lined up several dishpans, and
placed the pots in the dishpans. Boiled water, rapid boil, and
poured into the pots. Poured enough water in the pots to also
fill the dishpans about 1/3 full. Everything very hot and steamy
from top to bottom. The fragrance of cooked soil filled the air.

Let the whole thing cool down enough to plant seeds, put plastic
wrap on top of the pots secured with a rubber band, hang on the label,
and then time to go back to the boiling water process again.

Plants are upstairs in front of double doors, and it is quite warm
there, along with dry winter air. Heat rises ya know; wish it was that
warm downstairs. The plants (dip or tet) germinate within a week
after being in the fridge dry packed. I like dry pack due to less
moldy issues, and it keeps the seeds from germinating so I can
decide when to plant them, not the seed's decision.

I used to have so many gnats that I vacuumed them up to
knock down the numbers, but had to resume vacuuming
when new egg hatching occurred.

Works for me. I haven't seen a single gnat, seeds planted early October,
and I also do not have any potted house plants which might harbor gnats.

Shirlee do you keep your seeds in the small paper envelopes ?

Hi Mike, no I keep the seeds in little plastic bags
and the refrigerator temperature is between 39 and 40 degrees.

I have been sterilizing my soil, too, since I found fungus gnat larva in the first bag of soil used this year. Unfortunately, I had already planted 18 pots before I noticed them. I am going to sterilize all potting soil used for seedlings from now on.

I didn't see such critters in the potting soil or pine bark mulch
years ago, but if I remember correctly all that used to be sterilized
before these products were market ready.

Evidently, not a case these days. So, now I use gloves before
handling either since finding various unwanted critters. Of
course, finding a torn bag would be suspect as well. I check
for that when buying.

Lol Shirlee, I probably wouldn't have thought to vacuum up the flying gnats! Amazing is the number of good ideas people come up with, thanks to all.

I used some of my brain cells this season and used Captan powder mixed in with the seedling mix. For 1.5 months, I'm still gnat free. I used Pro-mix with Mycorrhizae that sat outside all summer. I'm happy!

50℉ is a good temp for nematodes and the kill can be 100% effective a virtual knock down at this temperature. In the basement put a seedling heating mat under the pots your treating with bacteria whether insecticidal or symbionts. Your current 50℉ temp will make them drowsy and want to hibernate.

The basement is a perpetual Fall temp soil, a good time to apply outside too in the Fall.

Bacterial applications work better in warmer soil. Many will not be effective until the air temp is consistently in the mid 80s. Many bacterial recommendations are made way too early in the season when the soil is still too cold and they will not be effective.

Bacterial products are on the shelves for the Spring planting madness for purposes of commerce more than anything else. That is why multiple applications are recommended. Selling more bacterial products but Unfortunately being used too early the bacterial product gets a track record they do not deserve. Encouraging people to choose less effective but more toxic chemical pesticide alternatives.

Multiple applications can be a flag for products that are ineffective from the start, usually from adaptive resistance and chemical remediation by the insects symbiont bacteria to the applied pesticide toxins.

Being informed and getting working experience with the biology of the all the organisms involved is fundamental to increasing the abundance of best recommendations.

Best time to apply bacteria after a week of mid 80℉ and at the end of the day and before a rain, a bonus if you can swing it, is a good measure for bacterial applications. Warm your water like you do for sourdough. With Bacteria a pinch is as good as a pound, you don't have to use a fire hose mounted on a 50 gallon drum.

Thanks for your very important info Frogfan!

My pleasure.

josieskid said:James, what does "feeling particularly "crispy" mean? Does the Bayer 3-in-1 work?

@josieskid
Sorry, been away for a few days. Spring potting, planting...

I meant to say "crunchy", a term generally used to indicate people who congregate around health food stores, recycling and eco centers.

Yes, 3-in1 works very well, but it's like killing mosquitos with a cannon. But, if I get an infestation and I'm out of Gnatrol, I don't really want to wait a week for the new bottle to arrive.

beenthere said:It would seem, from the posts, that the common denominator is growing in the basement? Is it the humidity?

A home provides excellent conditions for most plant eaters. Warmth, protection from predation, and trays of juicy seedlings growing in moist media.

I do see them outside in the fall and early spring. Breakouts seem to coincide with a new bag of soil, and also certain types of soil, perhaps the peat component. But outside, they don't really have much of an effect on mature plants, and I think their predators quickly multiply and catch up to them after a while, keeping them in check.

"Breakouts seem to coincide with a new bag of soil, and also certain types of soil, perhaps the peat component."

This is a real problem that has been occurring for many decades. The areas where the peat is harvested are too often over grazed and what happens is sedges and grasses, will recover in these areas before the sphagnum is allowed to grow back and dominate. Their bodies are included in the prematurely harvested peat and the flies feed on the debris of these higher plants. Their eggs and larva are bagged in the medium.

Among other things, I use flying insect killer spray to kill gnats around my indoor newly-sprouted seedlings and indoor potted daylilies.

When I saw an alternative spray from EcoLogic brand that touts it is "safe around children and pets" made with cornmint oil, cinnamon oil and clove oil I of course liked the sound of that and bought some to give it a try.

It does kill gnats on contact. However, it also appears that daylily leaves, and especially buds, do not like it. It formed spots on leaves and caused buds to shrivel and even die.

So I won't spray it anymore around my established daylilies in pots, and I don't think I'll risk it around my seedlings either.

Too bad it caused damage, Dennis. It did sound like a good alternative.

touchofsky said:My dad had a wheel come off, too. He actually saw it rolling down the hill ahead of the car. thank goodness he was able to get stopped safely.
My dad loved to tell a good story, and this became one of them!

Ok late to the game, only 6\5 months after this conversation took place, but I have to share......

To this day, 40+ years later, I can still remember my grandmother, brother and I driving down the road in Hawaii, in our not too old blue subaru wagon, right in front of my favorite beach, when all of a sudden the front passenger tire came off (of course, I was right there in the passenger seat)!!!!

My grandmother did a hell of a job getting the car to a stop and off of the road! I can remember seeing the wheel continuing to roll down the road!!

As I stumbled out of the car, maybe almost falling out of the car in disbelief of what had just happened, some kids come running up with the tire!!! "Hey we got your wheel!!!!!"

I miss my Hawaii days, but they don't have daylilies out there!!

No daylilies in Hawaii?