Sounds like you will benefit from getting to know the common Q&As over in the container forum. Container gardening is much different than in the ground, thus I'm not sure why any container fertilizer would be attracting maggot/flies. This is one of those things newer gardeners tend to stumble with, and is easily fixed next year. Information on this seems terribly over looked in all the TV shows, magazine articles , beginner books and sites, and that's a real shame.

Another part of the problem may be the potting mix you chose. So much on the market is less than desirable, but produced cheaply.

Cucumbers are particularly heavy feeders, so a more difficult thing for a newer gardener to grow well in a pot. Much more bang for your buck growing herbs, smaller determinate tomatoes, greens....

I consider the price I can buy veggies in the store when picking what I want to invest my time and money growing myself. 1 cucumber = 40 cents. 1 tomato = $1.50 and that is not going to have the flavor of my own plants. Cucumber plants put out about half a dozen edibles. Tomato plants a good 20 or 30 fruits min. Pot and potting mix=10 to 20 dollars+, then add the fert and water costs.

Your correct. You don't want to carry over problems from this cucumber to next years plants. But since this 'soil' is still fairly new and not completely broken down right now, how about potting up some spring bulbs and winter pansies ? Do they grow there ? Set this where it's seen from a window and enjoy.

Or maybe you have perennial herbs that grow there that would work well in that pot all year long? I find herbs do pretty well in potting mix about three years before the mix breaks down and I need to put then in fresh. Herbs because they prefer harsher conditions than many plants.

With a full yard and many pots also, I reuse potting mix as filler in bigger pots, then as it ages I put it in a garden bed or one of the compost piles. If the pot had a diseased plant, I then decide by what it was, if I toss the mix or put it in a hotter compost pile, where it gets cooked good and proper. So this situation is going to vary by each gardener. Balcony gardeners undoubtedly end up just tossing out older mix.

Sorry I'm not more familiar with what grows during the winter in NJ.

Good advice from plaidbird. I reuse last year's as bottom filler in next year's pots, sometimes adding screened compost. If it has tomato blight it isn't exposed at the surface to be splashed onto leaves. I buy a fresh bag to use for the top layer. Recycling lets me get a higher quality product for that bag that I do buy.

Curious what you used for fertilizer that attracted flies?

I grow peppers in containers because the nights are too cool to grow them in the ground with much success.

I'm sterilizing the potting soil for reuse by using doubled, clear plastic trash bags and solarization. The doubled bags allow the sun rays through the two bags, the space between then acts as insulation, heating it up. After an afternoon in full sun, its way too hot to touch.

But then I have some 50 containers, 7-10 gallons, and thats a whole lotta potting soil to replace.

Just picked roughly 3 bushels of peppers. Roasted the chilis and sweet red peppers yesterday, and boy does that smell good.

Thats a good idea, David. I'm going to use it.