How to get rid of mosquitoes, gnats and cockroaches

Reader and old friend Valerio wants to know how to get rid of mosquitoes, gnats and cockroaches.

    Growing up in Singapore, I'd had my share of mossies and cockroaches.

    Mossies love me in any country, any part of the world:  Singapore, Indonesia, Taiwan, Finland, Japan, France, Spain -- just to name a few.  Singapore people would console me by telling me that I had intelligent blood.

    So, my having fallen prey to mossies everywhere would say that I'm not the right person to ask about deterring them.  I can, therefore, only offer some ideas, which may or may not work.

Mosquitoes and gnats:  maybe try the wine bottle residue trick. (How to trap fruit flies: https://piccola-chinita.blogspot.com/2026/03/how-to-trap-fruit-flies.html)  

Cockroaches:  maybe have the wine bottle lying on its side (horizontally) for them to get in.  I don't know what cockroaches like, but I've heard that rotting fruit like plums have a high alcoholic content, so bees/wasps/hornets that feed on rotting fruit in the garden often get so drunk they can't fly.  Maybe throw an overripe plum into the horizontal bottle, leave it to rot in there, and see if cockroaches will go for it.

Mosquitoes:  one method that's supposed to help (deter them) is to take Vit.B7 or B12, but googling tells me "there's no scientific evidence".  For sleeping, the best is a mosquito net, which is very common out in the tropics (and other parts of China), but you'd still need a solution for when you're not able to stay in bed.

Sticky glue paper:  the French farm that I used to go to and a restaurant in S.E. China hang them from the ceiling for the huge population of flies they get, but it looks gruesome with the flies stuck to them -- you have to leave them there for a while, as you can't keep replacing them.  If you want to try them (if you have beams), make sure they're higher than the top of your head, so that you don't walk into them.

Flies and mosquitoes:  one common Chinese practice is to hang a bead curtain in the doorway.  Flies and mosquitoes are supposed to be unable to negotiate the bead "wall" which will still allow air to circulate in the hot weather (vs a solid door).

For any flying insects:  I've seen those lamps (that emit a UV light) which attract insects and electrocute them.  Googling tells me that they're called UV Light Bug Zapper.  (From googling) UV light insect traps use 365nm wavelength tubes to attract flies, mosquitoes, and moths, killing them via high-voltage grids or adhesive boards. Suitable for indoor/outdoor use, popular models include AspectEK and FanFuGuo 20W lamps. They offer a chemical-free, hygienic pest solution, often requiring UV bulb replacements every 12 months for maximum efficiency.

(From googling in Chinese; translation by google translate)

Cockroaches:

自然处理蟑螂的核心在于“物理阻隔+天然毒饵+驱赶气味”。最有效的方法包括：用硼酸+砂糖（1:1）制成毒饵；利用小苏打+砂糖诱杀；使用肥皂水直接喷杀；以及在角落放置薰衣草、薄荷、香茅或柠檬精油 以驱赶它们。同时，保持家居环境干燥和清洁是根除的关键。

The core of natural cockroach control lies in "physical barriers + natural poison bait + odor repellent". The most effective methods include: making poison bait with boric acid and sugar (1:1); using baking soda and sugar to lure and kill them; spraying directly with soapy water; and placing lavender, peppermint, lemongrass, or lemon essential oils in corners to repel them. At the same time, keeping the home environment dry and clean is key to eradication.

Mosquitoes

使用自然方法处理蚊子，核心在于“物理阻隔”、“环境清理”和“天然驱避”：安装纱窗、蚊帐以阻隔蚊子；清除花盆、水缸等处的积水以杜绝滋生；利用香茅、薄荷、迷迭香等驱蚊植物 或艾叶、柑橘皮点燃产生烟雾来驱赶；同时使用电蚊拍或捕蚊灯辅助杀灭。

The core of using natural methods to deal with mosquitoes lies in "physical barriers," "environmental cleanup," and "natural repellency": installing screens and mosquito nets to block mosquitoes; removing stagnant water from flower pots, water tanks, etc. to prevent breeding; using mosquito-repelling plants such as citronella, mint, and rosemary, or burning mugwort and citrus peels to produce smoke to repel them; and using electric mosquito swatters or mosquito lamps to assist in killing them.

How to trap sea fish (Singapore)

This is a method of night sea fishing using a kelong -- a Malay word for a fishing platform sitting out at sea on stilts.

(from googling)

Quote

A kelong is a traditional offshore wooden fishing platform or stilts-based structure commonly found in the waters of Malaysia, the Philippines, and Indonesia, used for fishing, fish farming, and sometimes as a dwelling. These structures are typically built using timber, nibong palm, and rattan, and are often used to catch fish by, for example, lowering large nets at night.

Unquote

    It works, in principle, like how the wine bottle traps the fruit flies -- see blog https://piccola-chinita.blogspot.com/2026/03/how-to-trap-fruit-flies.html.

    As bait, a lamp is suspended over the submerged net (like the residual wine at the bottom of the bottle), which the fish all around can see in the dark sea.  The fish will swim towards the light, but once there, they can't see their way out.  The fisherman just has to raise the net at regular intervals.

    Back in 1973 or 1974, one of my maternal cousins owned a kelong, so my eldest sister, who was always coming up with novel ways for her group of friends to spend their weekends, approached him about letting her and her friends spend Saturday evening there.  I tagged along with a friend (Cheok Ah Hua from secretarial school).

    We arrived just after dark (which is 6.30/7pm in Singapore, one degree north of the equator).

    My cousin's kelong had raised walkways (on stilts) around the rectangular area where the net sat in the water.

    On the side of one walkway was an extension which housed the fisherman's sleeping quarters.

    On the side of another walkway was an extension which housed the kitchen and a room next to it, where my sister and her friends set up a table for mahjong and one for poker, for them to party through the night.

    Ah Hua and I went to another walkway where we lay down to watch the starry sky and listen to the lapping of the sea water against the stilts -- and doze off within no time at all, as it was nice and cool in the tropical setting.

    Every two hours or so, the fisherman would get up from his nap and raise the net.  My sister and her friends would pick what they liked from the catch, e.g., prawns, squid.  The sea food was so fresh that it was tasty as it was without much cooking needed.  We could just rub the prawns between our palms to partly cook them (and eat straightaway), or dip the squid briefly into boiling water, then into our mouths.

    The next morning, a Malay man in a sarong and a sampan boat approached the kelong. 

    It turned out that he had a long-standing arrangement with the kelong.  Every x months, he'd come along and scrape off the mussels growing on the kelong stilts in return for a sampan-load of mussels which he'd take back to shore, to shell and dry in the sun -- either for his own consumption or to sell somewhere.  What timing!  What a treat it was for us to be present to watch this cleaning process, as (according to AI) it takes something like "6–12 months for mussels to grow to marketable size" for tropical waters.

    Ah Hua and I lay on our tummies on the floor of the fisherman's sleeping quarters, stuck our heads out of an opening in the wall that came down to the bottom of the floor, and watched the proceedings right below us.

    The man removed his sarong, and dived into the water.  No goggles/mask, snorkel or a swimming cap.  Very simple mode of operation, which is enough in tropical waters.

    Within a few minutes, he surfaced with a cluster of mussels (yes, they grow in clusters, primarily for stability against waves, among other things), which he tossed into his sampan.  This was repeated until he'd filled the first sampan, which the kelong man then emptied (for the kelong).

    Something like another three or four loads later, the Malay man went back to shore with the last load for himself.

    Such a simplistic life style.

    Googling kelong tells me that:  Quote Many are now tourist destinations offering rustic, off-grid fishing stays.  Unquote

    I must've been one of the last to have experienced the kelong as a real-life work concept.  Maybe my eldest sister was to blame for having used it for a novel Saturday night party experience, with everyone following suit...

(Singapore, 1973 or 1974)

sampan:  [from googling] traditional, flat-bottomed Asian wooden boats (8–30 ft) with optional shelters, often used for coastal transport or as homes

How to trap fruit flies

Fruit flies have an incredible sense of smell.  It takes about two seconds (if not one) for them to zoom over to the source of something like a fruity smell -- as I've discovered from experience.

    For trapping them, I have used plastic bottles with a wide mouth, filling the bottles with some bait like fruit peel or fruit-infused liquid.

    I also add things like stones of fruit to shake around to kill them once they get in.

    The latest is wine.  It sounds like an expensive way to go about catching fruit flies, but one doesn't completely get rid of the contents of a wine bottle, even after tipping the bottle over to let it drip out as much of the liquid as possible, so that can be your bait.

    Leaving a wine bottle sitting around after pouring out the contents works well because the fruit flies will home in on the bottle and travel down to the bottom.  For some reason, they don't seem to be able to find their way up and out of the 75cl bottle.  Maybe it's too far up for them to fly, and the mouth is also too small for them to find the exit?

    No work needed at all -- except to drink the wine...  (For non-wine drinkers, I'll have to write another blog.)

“Huh?!?” conversations: 03 (UK)

I was forwarded a text from a group called The Tree Musketeers:

Quote

From the Tree Musketeers today:  If anyone would like any 2yo trees for free, you can come and get them today, Friday and next Wednesday from the Tree Musketeers Tree Nursery at Hackney Marshes.  There are elder, cherry plum and rowan going begging, all around 1-2m tall. They’re beautiful trees but we have to take them out of the field now and it’s too late for the council to use them for street/park planting. Please spread the word, I’d love to find homes for them. You’ll need a car or bike trailer unless you live very nearby.

Unquote

    I then forwarded it to a number of people I know who have a garden or might know people who might be interested.

    That evening, I was at a church dinner with one of the people I'd forwarded the text to.  Here's the conversation that ensued across the table (let's call her Fu Lay):

FL:  What kind of trees are they?

Me:  It's in the text, which tells you that they are cherry plum and some others.

FL:  How big are they?

Me:  It's in the text, which says that they are 1–2m tall.

FL:  How old are they?

Me:  It's in the text, which tells you that they're 2 years old.

FL:  Ah, I didn't understand the "yo" bit.

(London, 2026)

Playing football for Raffles Interact (Singapore)

Chatting (via WhatsApp texting) with a student in the Tuesday Mandarin group, now in her early 80s, about our earlier school days (hers in Lancashire, mine in Singapore) and the kind of school activities then.

    Her talking about playing hockey brought back memories of my playing hockey for the Raffles Interact (or the Interact Club of Raffles Institution) for their friendly inter-club competition with other schools (https://piccola-chinita.blogspot.com/2026/03/playing-hockey-for-ri-raffles.html).

    I was also recruited for their football team for the same event.

    As I'd never played football before (having played netball at the convent school, with football being played by boys only [during my days]), they said I could be goalie, as there was usually nothing to do.

    Which was true -- until the ball approached my goal at one point. My reaction was to go towards the ball to stop it.

    When I next opened my eyes, I saw all these faces in a circle above me, peering down in concern at me lying flat on the ground.

    I had stopped the ball indeed. It'd landed on my head and knocked me out. Quite a header, that.

PS:  For some reason, they never asked me to play football again for them the following year...

(Singapore, 1971)

* Googling tells me that the RI Interact Club is the oldest interact club in Singapore, formed in 1963.

(from googling)

Quote

Raffles Institution (RI) Interact Club is a service-oriented CCA [Co-Curricular Activity], guided by the motto "Service above Self," focused on community service, leadership, and international understanding. Members participate in weekly, hands-on community service projects — including befriending seniors, mentoring youth, and food preparation—along with organizing day camps and attending, leadership training.  

Unquote

(from googling)

Quote

Raffles Interact is a premier service-based Co-Curricular Activity (CCA) in Raffles Institution (RI), focused on community service, volunteerism, and developing empathy with the motto "Service before Self". It offers students, known as Interactors, opportunities to engage in weekly volunteering, mentorship, and large-scale projects to aid the underprivileged, elderly, and those with special needs.

Unquote

Playing hockey for Raffles Interact (Singapore)

I was chatting (via WhatsApp texting) with a student in the Tuesday Mandarin group, now in her early 80s, about our earlier school days (hers in Lancashire, mine in Singapore) and the kind of school activities then.

    She said she was always getting elbowed in the eye during netball, but got her revenge on a tall girl whom she particularly disliked by tackling hard during hockey.

    This reminds me of a time during Pre-U 1 (1971) at RI (Raffles Institution) when I was recruited by Raffles Interact (or the Interact Club of Raffles Institution) for their friendly inter-club competition with other schools.

(Googling tells me that Raffles Interact is the oldest interact club in Singapore, formed in 1963.)

    Being a sprinter, hurdler and long jumper, I was only able to take part in the running events as a full and proper participant.

    The RI hockey cohort had enough people for two teams. Team A won in its group, Team B "won" in a walkover in its own group, so the final game was between RI Hockey Team A and RI Hockey Team B, played on the field opposite SJI (St Joseph's Institution) on Bras Basah Road. (Maybe it belonged to them.)

    I was recruited for Team B as they were one player short last minute, given rudimentary lessons in handling the hockey stick, and assigned the goalkeeper position, as it's the least active one, I was told.

    At one point, Spencer Khoo in Team A was approaching my goal with the ball. I ran up to intercept it, and swung my hockey stick at the ball. There was a thwack and a loud "Ow, Pheng!" (my Chinese name) from Spencer that could be heard for miles away. He collapsed onto the ground, clutching his knee in agony.

    Well, I did stop him (a school team player) scoring a goal for his side.

PS: They never asked me back the following year to play hockey again for them. I wonder why...

(Singapore, 1971)

* (from googling)

Quote

Raffles Institution (RI) Interact Club is a service-oriented CCA, guided by the motto "Service above Self," focused on community service, leadership, and international understanding. Members participate in weekly, hands-on community service projects — including befriending seniors, mentoring youth, and food preparation—along with organizing day camps and attending, leadership training.  

Unquote

(from googling)

Quote

Raffles Interact is a premier service-based Co-Curricular Activity (CCA) in Raffles Institution (RI), focused on community service, volunteerism, and developing empathy with the motto "Service before Self". It offers students, known as Interactors, opportunities to engage in weekly volunteering, mentorship, and large-scale projects to aid the underprivileged, elderly, and those with special needs.

Unquote

Read also: Playing football for the RI (Raffles Institution) Interact Club

https://piccola-chinita.blogspot.com/2026/03/playing-football-for-ri-raffles.html 

Senior moment (London)

 

A friend, who's retired but still freelancing a bit, has been frightfully busy with all sorts of demands made on his time, so I have to keep reminding him that my text messages to him (which are usually about gardening matters) are almost never in urgent need of instant attention, unless marked as such.

    He texts me saying that if he doesn't reply immediately, he'll get busy on other things and only remember much later, calling it "a privilege of getting older".

    In consolation, I texted back with:  Haha, you’re not alone in this.  I was talking to a Tuesday Mandarin group student, aged 84, last week.  She said she’s starting to misplace things more and more.  She found a light jacket/coat thing the other day in her flat, and thought she’d taken someone else’s home from the swimming pool (she swims regularly).  Turned out to be her own!

(London, 2026)