H2O retention/pest control (potted plants)

[Ostrodamus]

I am embroiled in an ongoing battle with both pest control (gnats) and water retention in my indoor potted plants. With my time constraints (newborn primarily) I'm having a difficult time keeping things sufficiently moist without overwatering. They are in a greenhouse which means they dry quicker due to the lights and fans. I tend to need to overwater just a bit to compensate for my lack of routine. I'm finally going to add something to the top of each pot to help with both issues. I would like to go the route of pebbles/stones/rocks and wanted to know what other suggestions people have. I found a bulk bag of aquarium gravel that I was thinking of using. They would be rinsed thoroughly, and I would be bottom watering the pots which should reduce the chance of any potential harmful influence from them.

In my pots, I'm running a roughly 40/40/20 ratio of potting soil/coconut coir/perlite.

Failed attempts:
Sticky traps (still currently using, but they fill up constantly)
Sand (contrary to belief, gnats will still burrow)
Coconut coir top layer (gnats will also still burrow)

Thoughts?

 

[Meadowlark]

Have you considered adding something to the bottom of the pots?

... add something to the top of each pot to help with both issues.

Specifically, I'm thinking I would try a quasi-Hugenkultur approach by lining the bottom with decaying/rotted small pieces of water soaked wood . I have found this a very effective technique in raising veggies, especially leafy ones. The wood seems to release moisture at a rate the leafy plants like...but you do have to keep watering regularly.

I have not tried this myself on house plants but I think it would be well worth a try...especially on leafy plants in fairly large pots.

 

[Anniekay]

BTI added to the water you use to water the plants is supposed to work. It builds up in the soil and destroys them. I think just bottom watering will help as they say that not letting the soil dry on top is what makes them attractive to your soil. That said, when I get them inside on my new seedling's soil I use cinnamon but it isn't effective long term. I think the gnats get used to it. Since my seedling will go outside I don't have the problem after they get planted out.

 

[Tetters]

During the winter months your indoor plants need a rest. They do not need any water at all until the compost in the pot is very dry (with one or two exceptions) Water thoroughly much less frequently, and when you do allow all the water to drain away through the bottom of the pot.
The compost needs to be very gritty to allow drainage, and the pot containing the plant should, ideally be placed onto a bed of pebbles in the outer receptacle.
In the winter, the plants should not stand in water at all, unless they are in a pond - that is the fastest way to root rot.
Occasional misting of the leaves can be beneficial, and damp dusting of large fleshy leaves.
This is how we should do it.
Unfortunately, I always tend to forget the plants indoors in favour of getting outside, and I usually lose them due to unintended neglect. I have very few now, and they are the ''easy'' ones that can put up with me.
''The spirit is willing, but the flesh is weak'' my old mum used to say........