Cockroaches in Valencia: why they appear and how to keep them out

They are almost always harmless, and their arrival usually has nothing to do with how clean your flat is. The giant cockroach you meet on a July night in Valencia is a seasonal, outdoor visitor that climbs up from the sewers and drains when the weather turns hot and humid. Meeting your first one is practically a Valencian rite of passage. Here is who she is, why she appears, whether she is dangerous, and how to keep the visits to a minimum.

Who is this lady?

The star of the Valencian summer, the big reddish-brown creature that makes you scream like you are in a horror film, is nearly always the same one: Periplaneta americana, the American or "red" cockroach. Three to four centimetres long, endless antennae, the build of a small tank and, crucially, it flies. Well, it glides. Clumsily. Usually straight towards the lamp, which means straight towards you. That is the exact moment you discover you can leave a kitchen by leaping over a table.

Its smaller, more discreet cousin is the Blattella germanica, the "blonde" or German cockroach: one to two centimetres, beige, and the one that genuinely moves in, settling into the warm corners of your kitchen. Less dramatic, but far more persistent.

Why does she turn up, especially in summer?

Good news for your ego first: the big red cockroach is generally not a sign that your flat is dirty. That one comes from outside - specifically from the sewers and drains, where it is warm, humid and dark, exactly her idea of paradise. When temperatures climb and the air fills with Mediterranean humidity, she works her way up through pipes, drain covers and even palm trees (yes, some live inside palm trunks) to explore the world. And the world, sometimes, is your bathroom.

So this is a seasonal, urban phenomenon, typical of hot cities around the Mediterranean. The warmer the night, the more active they are. The cockroach is not a personal curse: it is simply the month of July.

Is it dangerous? (the reassuring part)

Second piece of good news: no, she is not going to attack you. The cockroach does not bite, is not aggressive, and her main weapon is the speed at which she vanishes under the fridge. That said, let us stay factual: because she wanders through the sewers before turning up at yours, she can carry germs on her legs. This is not cause for panic, just basic hygiene: wipe down any surfaces she may have visited, and do not let her settle in for good, especially the indoor blonde variety.

How to keep the visits down

We will not pretend otherwise: you cannot eradicate the Mediterranean. But you can seriously cut down the appearances, and it mostly comes down to one word - drains.

The most effective habit, and the least known: block your plugholes at night. A stopper in the sink, the shower drain closed, and you cut off their favourite motorway. Then the classics: do not leave food or dirty dishes lying about, take the bin out in the evening, seal gaps around pipes and under doors, and check the air vents. For the blonde cockroach already indoors, gel bait traps from a pharmacy or hardware shop work well; for a genuine infestation, call a pest-control firm. As for the city, the municipal services treat the sewer network regularly, especially in summer - which is also why, on certain nights, you suddenly meet several of them at once, fleeing the treatment.

Learning to (almost) love her

Deep down, the cockroach is part of the folklore of the Valencian summer, just like the mascletà that rattles the windows or the terraces still packed at one in the morning. It is the tiny price of a climate where you live outdoors eight months a year. The old-timers will tell you with a very local shrug: es lo que hay, that is just how it is.

So the first time, yes, you will scream. The tenth time, you will pick up a glass and a piece of cardboard with the calm of a veteran. And one day, watching a newcomer bolt out of their kitchen in pyjamas, you will smile, because you will know: they have just passed their entrance exam too. Welcome to Valencia.

Sources

• Ajuntament de València - municipal pest-control and sewer treatment information
• Generalitat Valenciana - public health guidance on urban insects

Information verified in July 2026. The Daily Valencia is an AI-assisted publication with human review; spotted a mistake? Drop us a line.