Chances are you get occasional houseguests you’d rather not have visiting. While I can’t help you with the two-legged kind (though putting them to work often helps move them along), I can offer advice for dealing with pests of the insect variety—without resorting to nasty chemicals that are bad for you and the environment, OR spending a mint to eradicate the little buggers.
As a general rule, your first line of defense is to keep pests out by sealing cracks, using repellents, screening openings, and not bringing any stowaways home. Should any make it inside, most of them can be trapped pretty easily if you have the right bait, like their favorite foods or natural critter-specific chemical attractant scents called pheromones.
About this time of year, I often have some small kitchen guests. It’s an inevitable fact of spring: Sugar-seeking ants find their way in through some infinitesimal crack and start casing the joint. Once they find crumbs or other spilled food, the news spreads like wildfire through the colony, and soon there is a tiny two-lane highway full of ants carting away my leavings.
Reduce your chances of an ant invasion by keeping spills cleaned up and food stored in secure containers. Seal any cracks with caulk and sprinkle entry areas with crushed dry mint, ground cinnamon, or cloves to keep them out. Also, clean the floors, counters, or any other surfaces where you’ve spotted them as often as you can, so you’ll remove the trails that they lay down to lead their fellows to the food.
If you can’t stem the invasion that easily, you can use a sugar-borax paste to control the ants. Borax is reasonably safe for humans (you still don’t want to eat it, or allow kids to play with it, so keep it off food and out of reach of little hands), but when the ants carry it back to their colony, it kills the whole nest. Mix 1 teaspoon borax or boric acid and 1 teaspoon sugar or honey with enough water to make a thin paste, and put the mix in a small jar near where the ants have been foraging. Refill as needed until it no longer disappears. You can also buy ready-made liquid natural ant killer that contains borax and sweetener.
Pantry Moths and Flour Beetles
Just about any time of the year, you may find you have been unwittingly hosting tiny banquets in your dry foods. If you see small (½-inch-long) grey-brown moths flitting about, or you open a food container only to find the contents full of webbing, you have pantry moths. Tiny black or brown beetles found in flour or other ground products are flour beetles. Your first response should be to put affected containers in the freezer for a day or two to kill the adults, and then get the tainted food out of the house and into the compost or trash (or, at our place, the chicken feeder). Check other containers and deal with other active infestations at the same time. If you don’t want to discard food products that may be lightly affected—such as a jar of whole beans with a few moths strolling around on top (more protein, according to my mom)—store them in the freezer until they’re used up.
These small munchers usually arrive in purchased food (including pet food), so buy sealed containers and shop at places with clean shelves and high product turnover. Store bulk foods in containers or glass jars that seal tightly (plastic bags won’t keep determined pests in or out for extended periods), and/or put purchases in the freezer for 3 days when you bring them home to kill any adults hiding inside (eggs take more like a month to kill). As for the moths that are already loose in your house, it may take a bit of work to get rid of them, but if you stay vigilant, it can be done. Clean up any spilled food in storage areas and make sure all food is kept in sealed containers. I put an intact, dried bay leaf in each container, which is perfectly harmless to humans but seems to help keep pests away.
If you have a bad case of pantry moths, you may want to invest in some pheromone-baited traps to help thin the population, or keep one around all the time to alert you at the first sign of a problem.
Smaller (¼-inch) moths flitting around in places away from the pantry may mean you have clothes moths. They eat wool (clothing, blankets, carpets, felt), fur, and even animal-hair bristle brushes. Vacuuming every nook and cranny of storage closets and bureaus will help control them. Soaking woolen items in hot water (temperature above 120°F for 20 to 30 minutes) will kill moths and their eggs, as will stashing them in the freezer for a few days. Large items such as rugs and furniture can be “fumigated” with dry ice. Store clean woolen items in sealed heavy-duty bags to help keep moths out when you won’t be wearing them for a while. Small cloth bags of dry lavender, rosemary, or cedar chips will help repel moths—but you need to replace them at least yearly. Cedar chests and closets look nice, but don’t count on them to do much in the way of repelling after the first couple of years. Avoid moth balls, as they are very toxic to humans and pets.
You can also buy pheromone-baited clothes moth traps; use a bunch to control an infestation, or keep one around to alert you to budding invasions.
Living way out in the country and well north of the Mason-Dixon line, I thankfully have yet to meet a cockroach on my home turf. But I hear they can be enthusiastic houseguests. Even if you don’t have your own domestic population, you can unwittingly import roaches in boxes or items that were stored in an infested building, so have a care with stored items. Many years ago, I came to work to find my new phone encased in a clear plastic bag with a bit of pest killer inside: Evidently the new phones that had just been installed throughout the building had spent a little too long in a warehouse and had become roach motels...and now the critters were checking out. Since they can spread disease and aggravate allergies, it is important to keep cockroaches under control. But not by turning to highly toxic chemicals.