Don't let fruit flies ruin your harvest.
It's amazing how fast fruit flies move in (and how annoying these embarrassing pests can be) when you bring your harvest of homegrown fruit into the kitchen. Fortunately, there are environmentally friendly ways that will rid your home of the pesky invaders. Begin by making sure that all sink drains are clean. If possible, cover fruit in airtight containers or store it in the fridge, although it's often necessary to leave fruit such as pears and tomatoes on the counter to allow them to ripen. Make a highly effective fruit fly trap by placing cracked and slightly overripe tomatoes in a plastic tub. Cover the tomatoes about 1/3 deep with vinegar. Put the lid on the container and poke gazillions of pen point sized holes in the lid. Place near the fruit and replace when it gets gross.
Another simple trap consists of a bowl of sweet wine and drop just a touch of dish soap on top. Barely touch the surface of the wine at the center with your fingertip to break the surface tension. The fruit flies will be attracted by the scent of the wine, get stuck in the soap and it's goodbye Charlie.
Another trap is to use apple cider vinegar. Heat up a half cup or so of apple cider vinegar and pour it into a jar- it just needs to be deep enough for the flies to drown-and add a drop or two of dish soap. The dish soap will break the surface tension of the liquid so the flies can’t just sit on top and fly away when they’re done. Roll up a piece of paper and insert it into the mouth of the jar to form a makeshift funnel and tape it in place. The flies will go into the jar to get at the vinegar but won’t be able to figure out how to get out, and will drown.
For fun, supplement your fruit fly control program by growing a couple of sundews (Drosera) in your kitchen. Place the pots in a saucer filled with enough water so that the bottom quarter of the roots remain submerged. The sticky leaves secrete sweet juices that attract and then digest fruit flies (and a lot of other interesting bugs) by the gazillions.
You can also buy non-toxic fruit fly traps at Ace Hardware According to folks who have used them, they are highly effective.
I've also heard, but haven't had time to test the theory, that placing a sprig of rosemary in with the fruit makes the flies go away.
Finally, to knock down populations quickly, use your vacuum cleaner hose attachment to suck the flies out of the air. This method is so much fun; you'll actually be disappointed when all the flies are gone.