Nearly everything that makes bed bugs difficult to get rid of follows from the way they grow. They develop in stages, each gated behind a meal, and one of those stages sits inside a shell most treatments cannot reach. Once you can see that sequence, a treatment plan stops being something you take on trust. It also settles the question we are asked here more than any other: whether a Phoenix summer is quietly doing some of the work for you.
Five stages, and a blood meal for every one of them
Bed bugs belong to a family called Cimicidae, every member of which feeds exclusively on blood. Some of its species are adapted to bats and birds and stay with them, which gives you a quick sanity check: if the insects in your home are not closely associated with where people sleep and sit, the University of Arizona’s Cooperative Extension notes they may well not be bed bugs.
A bed bug passes through seven phases: the egg, five immature stages called nymphs or instars, and the adult. There is no grub, no pupa, no cocoon stage where it disappears and re-emerges as something else. A hatchling is a smaller, paler copy of the adult and behaves like one straight away, which is why the young are so easy to miss.
What matters is the toll paid between one stage and the next. An insect wears its skeleton on the outside, so it cannot simply expand the way we do. To get bigger it has to shed that casing and form a larger one, a process called moulting — and it cannot moult until it has fed. The Arizona Cooperative Extension states it in a line: bed bugs need to feed on blood at least once during each life stage. Five stages, five compulsory meals, before the insect can breed at all. Adults of both sexes then have to keep feeding regularly in order to reproduce.
So every bed bug in a house carries a feeding record behind it. A mature, breeding population is not a recent arrival that got lucky; it is evidence of at least five successful meals per insect, taken over weeks, from someone sleeping in that room. That is the most useful thing the life cycle tells you, and it is why a technician worth hiring reads a room rather than simply spraying it.
Egg
About one millimetre, pearl white, marked with a dark eye spot once it is more than about five days old. At normal indoor temperatures it hatches in roughly a week.
Five nymph stages
A hatchling is about the size of a pinhead. Each of the five instars must take a blood meal before it can shed its skin and move up to the next.
Adult
Five to seven millimetres, about the length of an apple seed and roughly the width of a credit card. They neither jump nor fly, and they do not burrow into skin.
The eggs are the part that decides whether a treatment worked
A bed bug egg is about a millimetre long and pearl white, developing a dark eye spot after roughly five days. At the temperature an occupied home sits at, it hatches in about a week. A female lays one, two or more a day, and the University of Kentucky’s entomology department puts her lifetime output potentially in the hundreds.
Those two facts explain most of what people find maddening about bed bug work. The egg is sealed, tucked into a joint or a seam, and not breathing the way a moving insect is. Products that work on contact with an active bed bug do not necessarily reach what is inside one. A treatment can therefore kill every insect present on the day and still be followed, a week or so later, by a fresh generation hatching into an apparently clean room.
That is not a failure, and not a company inventing a second visit. It is the life cycle behaving as it should. It is also why heat is taken so seriously in this trade: sustained temperatures around 120 to 130°F kill the eggs as well as the insects. When comparing quotes, the question worth asking is not how strong the product is. It is what the plan does about the eggs, and when the follow-up is.
What actually draws them to you, and how close they have to be
Bed bugs find people by body warmth and exhaled breath. That is the whole of it. There is no blood-type preference that holds up, and nothing you are doing wrong summons them. They are also not brought in by pets, worth saying plainly because it is a common worry — bed bugs will take a meal from other animals if no human is available, but they are not generally introduced to a home that way.
The more interesting part is the range. Work summarised by the Virginia Department of Agriculture and Consumer Services indicates bed bugs pick up these cues only over very short distances — on the order of a yard for exhaled carbon dioxide, and less for body heat. They are not tracking you from across the house. They are sitting close by, waiting for something warm and breathing to come within about a metre of them.
This is why they harbour where they do. The US Environmental Protection Agency notes they readily travel five to twenty feet from an established hiding place to feed, and that radius is where the whole problem lives. It is also why a room can be genuinely infested while the rest of the house has almost nothing in it — they cluster around a sleeping person, because that is the only thing they can detect.
Why they do not bite you every night
A bed bug with a host available feeds about every three to five days, not nightly. A feed takes between three and twelve minutes, and the insects are most active between roughly midnight and three in the morning, when the person in the bed is deepest asleep. If hungry enough they will feed outside that window, but the rhythm is the normal one.
Two things follow, and both trip people up. The first is that a quiet night proves nothing. People routinely conclude a treatment has worked, or that they never had bed bugs at all, on the strength of two or three undisturbed nights — which is exactly the interval you would expect between feeds anyway.
The second is that skin reactions are a poor clock. Bed bug saliva contains an anticoagulant that keeps blood flowing while they feed. Some people come up in itchy welts; others never react at all. Among those who do, the Arizona Cooperative Extension notes the response can appear within hours, within days, or as much as two weeks after the bite. That lag is why infestations are so often noticed weeks late, and why counting bites is close to useless for judging a treatment. On health the position is settled: bed bugs are not known to transmit disease-causing pathogens under normal living conditions. What they reliably cost people is sleep, money and peace of mind.
Does a Phoenix summer kill bed bugs?
No, and this misconception costs people time. The reasoning sounds sensible: it reaches 115°F here, heat kills bed bugs, so summer must be helping. The flaw is that bed bugs never experience a Phoenix summer. They live indoors, within a few feet of a bed, in a house held somewhere around 75°F by an air conditioner running all day precisely so the people inside do not have to experience it either.
The temperatures that matter are far higher than a hot day outside and have to be sustained. Killing bed bugs and their eggs with heat means holding the target around 120 to 130°F, which is what a professional thermal treatment is engineered to do to an entire room. A summer afternoon in the Valley comes nowhere near that inside a mattress seam, and the roof cavity is not where the bugs are. Cold is no better: bringing a room below freezing for one to two weeks is what that route would take, which a Phoenix winter is never going to supply.
The controlled versions are things you can genuinely use. A clothes dryer on high is one, and the Arizona Cooperative Extension’s guidance is specific — keep it running at least 40 minutes after the items are already dry. For things that cannot take heat, a household freezer works the other way round, over about four days. The uncomfortable conclusion is that our climate does nothing to help and the air conditioning quietly does the opposite: a year-round conditioned interior holds exactly the band in which eggs hatch on schedule and nymphs develop at full speed. Phoenix is not a hard place to be a bed bug. It is a very comfortable one.
How long they last when nobody is home
The other plan people arrive at on their own is to starve them out: shut the room, move to the sofa, go and stay with family, wait. It is a reasonable instinct and it does not work, again because of the life cycle.
In a temperature-controlled building, bed bugs survive between about one and four months without a blood meal. In cooler conditions, around 55°F or below, that stretches to a year or more. Arizona homes are conditioned essentially all year, so the shorter figure applies here — and one to four months is far longer than anybody realistically leaves a bedroom empty. An adult’s whole life runs to something like ten months, closer to a year where conditions are favourable. Waiting them out means conceding the room for most of a year.
This matters more than usual across the Valley’s seasonal properties. In communities like Sun City and Apache Junction, where furnished homes and park models sit unoccupied through the hot months and change hands between winter visitors, an empty season sits comfortably inside the window a population can wait out. A home that was quiet in May can have somebody bitten in November without anything new having been carried in.
How a small problem becomes a large one
Under good conditions a bed bug can go from egg to breeding adult in as little as a month. Put that beside a female laying one or two eggs a day and potentially hundreds across her life, and the shape of the curve is obvious. Early on almost nothing is visible and nothing feels urgent. Then the second and third generations arrive more or less together, and what looked like an occasional bite becomes a room with a population in it.
In shared buildings the same arithmetic runs sideways as well as upwards, because bed bugs move between apartments through wall voids and along corridors. The trend is not in anyone’s favour either: residential cases in the United States have climbed since 2001, and resistance to common insecticides has risen over the same period. That is much of why the retail aisle disappoints — shop-bought products often kill the bed bugs you can see and leave the infestation intact.
One category deserves a blunt warning rather than a gentle one. Total release foggers — bug bombs — and aerosol sprays have not proven useful for resolving bed bug infestations, and the Arizona Cooperative Extension records that their misuse in homes has caused fires. They also push survivors deeper into voids and into neighbouring rooms, making the next attempt harder than the first. If there is one thing on this page to act on immediately, it is that the earlier a professional is involved, the faster and cheaper the whole thing is.
Where Arizona renters stand
Arizona is one of the states with a statute written specifically for this. A.R.S. § 33-1319 sets out obligations on both sides of a rental. The landlord has to provide bedbug educational materials to existing and new tenants, and may not enter into a lease for a unit they know has a current infestation. The tenant must not knowingly move infested items in, and on learning of bedbugs must notify the landlord in writing or electronically.
Two limits are worth knowing before you rely on it. The statute excludes single-family residences, so it is a multi-unit provision. And it expressly does not create a cause of action for damages against either party, so it does not answer the question most people want answered — who pays. That is a matter for the lease and, in a dispute, for a lawyer or a tenant advice service rather than a pest control company. What it does give a tenant is a clear procedural step: put the notification in writing, and date it.
What the biology means for getting rid of them
Put the pieces together and a sound plan defines itself. Because the eggs are protected, it has to account for what hatches after the first visit rather than stopping at what died during it. Because a quiet few nights is the normal feeding interval, progress has to be judged on evidence rather than on how anyone slept. Because the insects detect a host only from about a yard away, they concentrate near the bed, which is what makes focused work effective. And because resistance is real and rising, method matters more than product strength.
None of that requires you to become an entomologist. It does mean you can ask better questions of whoever you hire, and recognise a straight answer when you get one. If you have reached the point of wanting the problem dealt with rather than understood, our page on bed bug inspection and treatment covers how both actually run, what we need from you beforehand, and what it costs.
Bed bug life cycle questions
How long does it take a bed bug to grow up?
Under favourable conditions, as little as a month from egg to breeding adult. The egg hatches in about a week indoors, and each of the five nymph stages needs a blood meal before the insect can moult into the next. Cooler conditions or irregular feeding stretch that out considerably.
Do bed bugs bite every night?
No. With a host available they feed roughly every three to five days, and a feed lasts three to twelve minutes. A couple of undisturbed nights therefore tells you nothing either way, and a quiet week is not proof a treatment has worked.
Can bed bugs survive the heat in Phoenix?
Easily, because they never encounter it. They live indoors at around 75°F. Heat kills them at sustained temperatures of roughly 120 to 130°F — what a professional thermal treatment produces deliberately, and what a hot day outside never produces inside a mattress seam.
Can I starve them out by leaving the room empty?
Not realistically. In a temperature-controlled building they survive roughly one to four months without feeding. Since Arizona homes are conditioned year round, you would be giving up the room for months with no guarantee, while the population waits or finds someone else in the building.
What attracts bed bugs to one person and not another?
Body warmth and exhaled breath, detected only over very short distances — about a yard for carbon dioxide, less for heat. Where two people share a room and only one is bitten, the usual explanations are proximity to the harbourage and the fact that some people never visibly react.
Why did I only notice them weeks after they arrived?
Partly numbers, partly your own skin. A small founding population is hard to see, and it takes weeks of feeding and moulting to become obvious. On top of that, a reaction can take anywhere from a few hours to two weeks to appear, so the marks you are dating rarely match the night they were made.
Related services
Bed Bug Control
The practical companion to this page: how the inspection runs, heat against chemical, cost, and how we confirm it is over. Bed bug control.
Pest Identification Guide
Not yet certain what you are dealing with? Rule species in and out before treating anything. Identify what you found.
Commercial Pest Control
Hotels, student housing and multi-unit buildings, where movement between units is the problem. Commercial pest control.
Not sure whether what you have is established?
The life cycle tells you what to look for. We will tell you what is actually in the room, and say so plainly if the answer is that you do not have bed bugs.