Curious about cedar

I have read that cedar mulch or shavings is a good natural bug deterrent. If I used it on my houseplants as a mulch, would it prevent insects this winter if I used fresh potting soil too?

What kind of insects are giving you a problem?

Fungus gnats. I wanted to treat with beneficial nematodes last winter, but nobody carries them locally when it is cold. That is when I discovered the problem. As far as I know, with my new houseplants, I don't have a problem yet and I don't want to have a problem. Last year, I cooked the soil in the oven a few times and that didn't work.

Fungus gnats are generally a sign that you're watering too much. Sterilizing soil, etc can potentially help a little but if you are watering a little too much you're liable to have problems with them anyway. So if you're not having problems now, I'd just keep careful tabs on your watering habits. Once you have them, you can use mosquito dunks to help control them too--those may be easier to find than the nematodes.

I've found a great cure for gnats (it was posted on this site) slice potato's and put the slices on top of the soil for a few days, it worked for me.
Christine

I didn't know that. Thanks ecrane. The plants didn't seem to complain about how much I was watering, so it was not something I thought about.
I have tried vinegar and soapy water and that didn't hardly touch the problem. They came out of the bottom of the pot too, so I don't think a sliced potato would have helped either. But mentioning that made me think I should have realized that I was watering too much if they were living around the drain holes of the pot. Ha ha ha. Thanks a lot you two. If I see that I am beginning to have a problem again, I will let the soil dry out.
Here is another question. The plants we got that had the gnat issue, we got from Lowe's. We think they might have been already in the soil or something when we bought the plants. Because when we saw how well they were doing for us, we thought of buying more and saw the gnats crawling on the floor around the pots of plants. If a plant already has the problem, how would you solve it? We just decided not to buy anymore indoor plants from them once we saw that.

You could remove the plants from the pot and take off the soil without damaging the root system and re-pot in new soil. Good Luck !!!!

I will need it, thank you.

The fungus gnats lay their eggs in moist soil. Our local garden guru recommends putting about an inch or so of sand over the soil in the pot. According to him, the gnats won't lay their eggs in the sand, and eventually they will die off. I have not done this, so I'm not sure how long this would take because there will be more hatching going on until all the eggs gone.

The best cure is prevention, which actually hinges on two things, those being how light/heavy the hand on the watering can, and how well-aerated your soil is. Well-aerated soils make very hospitable homes for roots, and healthy roots are essential if a healthy plant is your goal, so much so that a healthy plant is impossible w/o a healthy root system. Adopting a free-draining, well-aerated soil and getting your watering on track should not only unburden you of the gnat issue, it will also provide your plants a much greater opportunity for them to grow much closer to their genetic potential (growth/vitality) than they might have in heavier, water-retentive soils.

The sticky at the top of this forum goes into a fair amount of discussion about soils (for your houseplants) and how to make or improve them - if you'd care to read it. If you find that info to be of value and want to read more, I can link you to a thread that explains in detail a concept that probably represents the largest forward step anyone growing in containers can take at any one time. Growing in containers is much easier than we sometimes make it, this, for wont of knowledge of how to cover the basics. For instance, I'm not being critical of advice already given because it can be helpful to a degree, but potato slices and covering the top of the soil with sand only treat the symptoms, leaving the underlying cause, the underlying cause being a combination of soil choice and watering habits that often finds the gnats cruising each other's homes in a cloud of orgiastic frenzy. Fixing the soil can actually take care of that over-watering issue by default, and eliminate the attractiveness of your chosen medium to gnats at the same time. Best luck, let me know if you'd like to learn more .......

Al

See what I grow houseplants in below:

Great advice Al, I havent tried your mix yet,how pricey is it to make a batch of it and is the stuff easy to find?
Thanks
Christine

Sometimes the ingredients are easy to find, sometimes difficult. It depends on what part of the country you live in. I also use the soil pictured below for many types of plantings. I think it's important to realize that it's not "my soils" that will make things easier on you and provide a more hospitable home for your plants' roots, it's understanding and being able to implement and manipulate the concept in favor of your plants that's the key. The recipes are simply the best or most practical way I've found of implementing the concept. I think that if there was a pivotal issue, it would be finding a bark that is suitable for either mix.

A 50 lb bag of Turface MVP + a 50 lb bag of grit + a 2 cu ft bag of bark costs me about $22, but you might expect to pay up to $30. You get about 3.5-4 cu ft of soil, or a little over 30 gallons after screening and mixing. The 5:1:1 mix, which is seen in the picture, is much less expensive, and ends up usually costing about half as much as commercially prepared soils based on peat - like MG or MGMC, Promix, and others. You do have to consider the effort it takes to get the materials and screen them where required. I don't usually need to screen anything for the 5:1:1 mix (in the picture), but the Turface for the gritty mix should always be screened, and the bark usually has to be screened, unless you're lucky enough to find prescreened fir bark, which is what I use.

Some pictures that might help, the first is the 5:1:1 mix.

Al

Thanks Al, I'll give it a try when I can get all the ingredients, although I wont be transplanting anything til next spring now that the fall is upon us.
Christine

I could go for that!! I have attempted to read the sticky, but it is more reading than I have the attention for. I do want to learn more though! Is your 5:1:1 mix the Turface:grit:bark?
Just so I know where I can start looking for the ingredients locally; where are you able to get your items?
If you never recommend sand, tapla, what would you recommend for grit?

This message was edited Sep 9, 2012 3:04 PM