Fungus Gnats? - Orchid Board

Wynter010Beauty · #1 05-25-2010, 12:16 AM

I've always had a fascination for orchids. A year ago, my fiance bought me my first Phal., and then about 6 months ago, he bought me another Phal. Two days ago, I bought a Catt. at lowes (its a "bag baby"). About 2-3 months ago I bought some new soil to re-pot the the Phal's into slightly bigger/more decorative pots. I believe the plant mix I bought was Better-Gro orchid bark mix (the contents were damp). I just recently returned home from being out of town where I bought my Catt, and I was going to re-pot it because it is in such a small pot. After re-potting it, I went to do my weekly watering of my Phal's and there were little black 'fruit fly' type bugs flying around, I squished about 10 of them with my hands, I then looked into the bark mix, and there are extremely tiny (practically microscopic), round-bodied, practically clear insects crawling around on the bark. I tried to chase one with my finger, hoping it would 'hop' (hoping it was maybe a springtail) but to no avail, it just scampered around quickly. Would you say these are fungus gnats? I only water once weekly, sometimes once every 8-9 days, and I fertilize with Better-Gro every other time that I water. I'm scared that this may be an infestation that may be hard to cure and I just brought a new baby plant into the apartment. Any information at all would be greatly appreciated. Oh, and I live in Pennsylvania. Thank you!!

Zoi2 · #2 05-25-2010, 01:02 AM

It sounds like your potting medium is staying too wet. Is it dry before you rewater and are your pots just big enough for the root mass? Here is a link on fungus gnats you might find interesting. Fungus Gnats
Joann

Zoi2 · #3 05-25-2010, 01:03 AM

Oops, I forgot....Welcome to the Orchid Board!
Joann

Wynter010Beauty · #4 05-25-2010, 01:16 AM

Thank you! Yes, it typically is dry between waterings. The only thing that I can think of.. is that I was speaking to someone on here the other day because i was having salt build up on the medium and found that I must not have been flushing the pot/medium enough between fertlizing. So, I flushed it very heavily, and it had remained very wet for a while. I read somewhere on there that you shouldn't buy the pre-dampened orchid bark mixes, and someone even said that they actually bake their mix in the oven before use. Have you ever heard of doing that? Reason I'm asking is I wonder if it'd be beneficial to take them out of their mediums and put the bark mix on a few baking sheets for a little while? I was also reading about Physan-20.. problem is I'm not quite sure where I'd purchase it from locally..

Wynter010Beauty · #5 05-25-2010, 01:19 AM

Oh, and as for the pot size, they're 8 inch pots. They do have a drain-hole that empties into a dish.

Izzie · #6 05-25-2010, 11:55 AM

Search 'fungus gnats' on this board and you'll get a plethora of great threads that might offer some insight.

As to round, clear, crawling insects, I'm not sure about that. Not well versed in insect pests yet.

Wynter010Beauty · #7 05-25-2010, 11:59 AM

Thank you, I did some reading late lastnight after I figured out how to search using this website. I plan on attempting to find Physan-20 locally.. as for right now, I grabbed some yellow construction paper and cut into long pieces and rolled them up and rubbed vaseline on them and stuck them on the outside edges of the pot to hopefully catch the adults. I'm just quite curious about the little round-bodied insects.. I wish I knew what they were and if the Physan-20 would help kill those off too. Does anyone know if lowes/home depot carry Physan-20? If it comes down to it, I'll order it offline. Thank you!!

Zoi2 · #8 05-25-2010, 12:15 PM

I don't know if HD/Lowes carries Physan products.
I would not reuse your potting media, even after baking it.
I believe 8" pots are way too big for your plants and that is probably one of the reasons for the gnats. The center of the media is not drying out but the top and sides are. Most HD/Lowes big bag babies are ready for 3-4" pots, the smaller ones 2-3" pots. Your phals should probably go into a 4-5" pot depending on the roots. Most orchids are planted according to root mass.
Joann

Izzie · #9 05-25-2010, 12:16 PM

I've never found Physan at HD or Lowes, but those on the coast have found it at there's.

I HAVE found it at larger garden centers and nurseries though.

The cheapest I've found it online is from Ray Barkalow.
https://www.firstrays.com/cgi/cart/commerce.cgi

Izzie · #10 05-25-2010, 12:18 PM

Joann makes some great points.
Plant in a pot that just big enough for the root ball- otherwise, the media takes too long to dry in the middle and it leads to rotting.

And of course, throw that old media out in the garden for mulch- no reusing.