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we've found that small gnats like to inhabit damp soil in our houseplants. since the gnat like to lay their eggs in damp soil - they can multiply quickly if you don't do something about it. and we are anti-chemical. the best natural cure we've found is to put a layer of sand on top of the soil - it prevents any eggs from hatching and reaching the surface. make sure there aren't any holes in the sand - or the bugs will find a way in/out.
once we started using the sand trick - no gnats - and our house is full of greens and we are happy.

What are those tree things in the bottom right picture? I love them! And does anyone have any pointers on good places to find nice plant pots (beside Ikea).

I have TONS of houseplants and have never had any sort of bug problem. My rule of thumb with any new plant (aside from African Violets because they're leaves can not be washes off with water) is to rinse the entire plant (undersides of leaves and all) very thoroughly as soon as you bring it home to make sure anything that it may have on it from the nursery/store is washed off. If it's warm enough you can hose it off outside.

An ounce of prevention is definately worth a pound of cure in this instance!

Best of luck to you...plants are WONDERFUL decor and will make your house a very happy and healthy home.

P.S. My favorite indoor plants that are also good for low-light situations are snake plant, pothos, Chinese Iron Plant, Peace Lily, Spider Plant. There are more but those are very easy to keep and require little water and light.

I am not the person to answer this because I kill most plants (unintentionally of course), but I thought I'd share MY bug story. I brought a basil plant home from the farmer's market, and noticed a leaf was sort of chomped on. What I didn't expect was to later find a huge caterpillar sitting on top. It must have retreated after eating the other leaf and then came out later for another meal. Ick.

Colellis: I had a HUGE infestation of gnats this summer, and couldn't figure out where the darned things were coming from! It may have been though the gaps between the window frames and my screens ... but I wondered about the plants! The gnats pretty much disappeared when the weather got really cold ... but when it warms up a bit, I still notice one or two.

I should add that I never had this problem before this summer... and some other folks in the neighborhood that I mentioned it to said they had it as well.

ARC,

those look like very healthy and largish Jade plants (Crassullae family)

For ARC - they look like very old jade plants - they can get very big. They don't like to be waterlogged (learned this the hard way) so make sure you have good drainage.

Pots - Chinese stores here (Vancouver) have beauties, as do most plant nurseries, and for really big pots cheap - Costco in the early spring.

One way to get rid of gnats - get that sticky yellow tape or cards they use to kill whiteflies. Cut strips of it that aren't very tall and line the inner edge of the pot with them, just between the soil line and the top of the pot. The gnats eventually bump into it as they buzz around, stick and die. I got rid of a huge gnat infestation this way in about a week.

Ants will set up shop in the pots of house plants once they get inside the house. We had to get rid of three plants that were basically nests of ants one winter.

I've been living in a humid climate for years and am very, very familiar with fungus gnats. They make me absolutely crazy. After lots of research and several of the above-mentioned methods (the tape, the sand, several kinds of bug spray that killed lots of plants despite their "green"-ness) the best way I've found to manage them year-round is letting the soil dry out very well in between waterings, which kills the larvae that live in the topsoil.

So if you're really worried about getting pests like that, the best thing I can suggest is only keeping succulents and the like that can tolerate drying out without getting too stressed out. (The few plants that I have that need lots of water I now keep in sealed terrariums, and they're quite happy and gnat-free.) So go for that jade plant!

Clementine and Sunspot42: Great tips! I'll give them a try if I have another problem.

Plants are a great room divider and privacy screen. The real risk of infestation is bringing something in with a new plant. The best way to avoid this is to go to a good nursery and garden center. Yes, you can get a good deal on some clearance thingie at the Home Despot, but who knows how long it's been sitting there and how well it's been been cared for? It's worth the extra money to go to a real nursery and talk to the employees there. Tell them about the place you want to put the plant, they will recommend some good choices to you, give you the lowdown on how best to care for it, and also give you tips (if needed) to make sure you don't bring uninvited guests in with you. Otherwise, in my years of experience, ants and other bugs come into your house for the same reasons you do -- shelter, food and water. Having a houseplant won't increase or decrease that problem. If you buy the plant from a reputable source, follow the advice from the experts at the nursery, AND you haven't had a problem with bugs already, you should be just fine.

That succulent on the top right reminds me . . . I buy succulents from Crate and Barrel, but sometimes they don't have them. Where else can I buy them already cut? I tried looking online for them but couldn't find anything that wasn't in soil.

Any bugs attracted by your plants are very unlikely to be harmful - in my experience, it's mostly ants, scale and gnats. Certainly the benefits of the plants far outweigh any problems with insects.

There are a few steps to take to lessen or completely remove any bug problems:

1. Use fertiliser. A healthy plant can fight bug attack better.
2. Use surface bug spray around corners if you notice ants trying to get in and set up a subcolony in the pots.
3. Rotate your plants so that they spend some time outdoors. Sun, wind and rain all make life difficult for bugs, especially scale.
4. Don't overwater - I water my plants once a week with a little liquid fertiliser in the water, and they're all very happy. Self-watering pots (where the plants draw from a reservoir in the base) are a good way to beat surface-dwelling gnats.

One of the little known facts about indoor plants is that pests can be airborne. Despite your best efforts, they can find your unhealthy plants. The best pest management and control is healthy plants and regular pest scouting. Use Neem Oil every five days or so if you do encounter plant pests. Log on to eBay and find a good quality 10x loupe at modest cost. Many plant pests are difficult to detect with the naked eye (mites in particular).

While you’re there, buy a digital foot-candle or lux light meter. Healthy plants start with adequate light. You’ll only need the meter to locate your plants. Then share it with your friends, relatives, apartment management or condominium association. You’ll do everyone a big favor. Using window direction for light measurement is utter nonsense.

The next best thing you can do for your indoor plants is to stop using drench and drain watering (I call it poke, pour and pray).

It’s the un-green way to water indoor container plants. The greenest way to water them is by sub-irrigation, erroneously called “self-watering” in the consumer market.

Retired NASA scientist, Dr. Bill Wolverton notes this in his best selling book How to Grow Fresh Air: 50 House Plants that Purify Your Home or Office . Read pp 34-37 in his book. Garden writers fail to mention these pages that speak about hydroculture and sub-irrigation being much greener methods than drench and drain top watering. Drain holes are good only for sinks and street corners, not indoor plants.

Writers usually only mention a catchy phrase (or title) such as “10 plants to clean your indoor air”. This is grossly misleading consumer information. It could lead to exacerbating someone’s allergy or other health problem. The subject deserves media attention. I’m working on it.

Some of the green benefits of measured sub-irrigation are:

• Keeping soil optimally moist rather than wet minimizes an exposure to propagating mold. It’s far more hygienic than top watering.
• With measured sub-irrigation the soil surface is always dry. This removes the habitat for the propagation of fungus gnats (Sciarid Flies). This is a particularly sensitive problem in and around food service areas.
• Significantly improves plant longevity or sustainability.
• Plants watered this way may have a beneficial affect on indoor air quality.
• Measured sub-irrigation conserves water.
• Use measured sub-irrigation for any plant species (including cacti and succulents) other than epiphytes.

Interior plant maintainers in Europe know about hydroculture and sub-irrigation. Unfortunately, indoor horticulture education in the U.S. is stuck in a prior century.

Bob Hyland
aka Greenscaper on the web
InsidePlantsLive.org

I believe that a bigger problem than plants attracting bugs is that plants can bring their own bugs home with them. Try to buy your house plants at a reputable shop. If possible (not this time of year for most of us) leave the plant outside or on a porch for a few days after you buy it so you can see if is carrying any passengers.
BUT... that is a manageable risk, easily offset by the benefits (environmental and psychological) that houseplants provide!!

For gnat prevention:

Put out a small bowl of water with some dishwashing liquid in it. They'll be attracted to that and then drown.

For severe, horrible gnat infestation:

Fill a bucket or your sink or tub with water. Completely submerge the plant, and the bugs will drown. (Optional step: quickly put a plastic or paper bag over the plant to keep some of the bugs from swarming away when you pick up the plant.)

Regarding cacti and succulents:

Mealybugs love them. After they've made a dent (literally) in your cacti and succulents (and my adenium), they'll spread to the other plants. Keep in mind that many plants that are not technically succulents have succulent leaves, like African violets or Swedish ivy. You must be vigilant and use a Q-tip with alcohol on the bugs when you see them. Even if you don't see them, give the plants a swipe every week. Pay special attention to the buds and axils. If the mealybugs get really bad, I spray them with Safer. I don't like it, but I'm careful to completely avoid my culinary herbs.