These beautiful plants really capture the essence of the tropical climates and make the owner feel like they are in a tropical rainforest.
However, there may be a problem lurking amongst your flowerbeds.
If you start seeing little dots moving amongst the leaves, you could probably hear other gardeners or horticulturalists groan for miles around.
These little dots are actually creatures called Thrips, and they are a nightmare for anyone with a green thumb.
They will destroy plants in your garden before you know it and will have you tearing your hair out trying to deal with them. So, what can be done about these little invaders?
In this article, we will look at Thrips, ways to prevent them, and ways to deal with them once they are here.
Everything You Need To Know About Thrips
Thrips are long, thin insects that normally have wings and can quite often resemble grains of wheat or rice when you first see them on the leaves of a plant.
But don’t be fooled, these little bugs are pests that carry vectors for many plant diseases that can be as damaging as the thrips themselves.
The insects are tiny in size, being only about 1 mm or less in length, but the sheer number of them that can appear can be devastating.
While they can be many colors, the ones that you will see on monstera are normally the black and yellow ones.
It is also interesting to note that they are not really closely related to any other insect, with their closest cousins being the true bugs, like the aphid or the cicada.
However, this doesn’t mean that there are a few of them, instead there are about 6000 different species, most of which are problematic for gardeners.
Why Are Thrips A Problem For Monstera?
Thrips are mostly keystone species that feed on a number of different things, depending on the species.
The ones that we tend to give people problems, feed on crops or plants in the garden.
The problem with these species is not the same as mites or aphids, as these two feed directly on the sap and only the sap.
Instead, a thrip will feed on the pollen, the outer layer of the plant’s epidermal (kind of like their skin), and the tender parts of the plant – flowers, new leaves, and buds.
Some species also create galls (egg chambers) within the plant, and the young inside will consume the plant’s sap.
Since thrips feed on almost every part of the plant, the plant struggles to feed itself or generate new food, thus killing it.
This is especially problematic with big plants like monstera.
The Life Of A Thrip
Thrips tend to live for about 60 days in total, including all stages, and generally have about two different stages of life that they go through.
The eggs are tiny, almost imperceptible to human eyes, and the females will lay them in the plant’s epidermal or on the underside of leaves.
These eggs will hatch and become nymphs, which are wingless, immature adults, that then begin to feed on the plant tissue to sustain themselves.
Between 8 and 15 days after birth, the nymph will go through a kind of living pupae phase where they still move around, before becoming an adult with wings.
These winged adults will live for about 45 days before dying, thus completing the lifecycle.
During winter, the remaining thrips will hunker down and hide, or if they are pupae, take a pause in development until it is warm again.
Thrips Place Of Origin
Thrips are pretty much found in all temperate, subtropical, and tropical climates. In fact, they are pretty pan global and take most environments where there are some trees in their stride.
However, they tend to thrive in warm temperatures, with their ideal temperatures being between 27 and 30 degrees Celsius or 80 to 85 degrees Fahrenheit.
They can survive as low as 10 degrees Celsius or 50 degrees Fahrenheit and as high as 32 degrees Celsius or 90 degrees Fahrenheit, but beyond these temperatures they struggle to survive.
As such, the closer you get to the poles of the world, the less likely you are to experience or see thrips anywhere.
How To Know You Have A Thrip Infestation
Unfortunately, with such a large plant as monstera, it is hard to examine all of it for a thrip infestation. However, the plant will tell you that it is having problems if you know what to look for:
Discolored Or Droopy Leaves
While monstera leaves do droop down a bit naturally, there is a big difference between the leaves being a droopy shape and the entire leaf collapsing along with the adjoining stem.
Normally, this droop coincides with the leaf going from a beautiful vibrant green to a faded yellow.
The reason is that the leaf is losing nutrients faster than it can replenish them, which probably means thrips are feeding upon it.
If it is only a bit yellow, then search for the signs of thrips and if it is fully yellow, the leaf might be beyond saving.
Black Spots Underneath The Leaf
Thrips generally like to stay underneath the leaves of a plant, so turning one over will give you insight into how the plant is doing and what unwanted invaders you may have.
If you can see a fair few tiny black spots on the leaf, give them a little scrap with something.
If they come off, then you know you’ve got thrips. Why? Well, that is thrip excrement or poo and thrips poop while they are feeding.
Counting actually might help you here, as thrips are hard to spot, and it will give you a clear indicator of how bad the infestation is. If there is a lot, then you need to take action immediately.
Curling Leaves
Droopy or discolored leaves are a pretty bad sign, but a yellow, curling leaf is a very bad sign. This normally means that the thrips have created galls in the leaf full of eggs, causing them to curl and die.
If you are struggling to see what creature has invaded your tree, look for curled leaves. If they are present, you have thrips.
Magnifying Glass
Sometimes the best way to work out if you have thrips is to find them yourself.
Thrips are hard to spot with the naked eye, but shaking a leaf over a white piece of paper can shake them loose onto it.
Their bodies will show up easily against the paper, and using a magnifying glass will confirm that they are thrips.
You could always use the magnifying glass on the leaves as well, but that will take a bit longer.
Saving Your Monstera From Thrips
Thrips are hardy creatures – you have to be when you are that small – and they reproduce quickly.
This makes them extremely difficult to deal with and because of the size of monstera plants, damage control can be a bit problematic as well.
As such, as soon as you find out about the thrips, you need to take steps to deal with them and most are easy to do:
Sticky Bug Traps
Sometimes the best methods for dealing with an infestation are the simplest. Making a few sticky bug traps and surrounding your monstera with them is one of the easiest.
In fact, this method works much better with thrips than other insects, as thrips have an unusual method of flying called the ‘clap and flap’.
This method of flying gets them from A to B, but it makes them incredibly bad flyers that can’t change direction in the air.
As such, when they fly towards the sticky trap, they will be caught no matter what. All you have to do is to make the trap enticing, which is easily done by making it an attractive color.
Thrips are specifically attracted to the colors white, yellow, and blue.
You can buy these traps online or in a gardening store, and they are usually pretty cheap.
Alternatively, you can make them yourself. All this requires is a colored card, string, a stick, and either honey, non-stick glue, or Vaseline.
Poke a hole in the top and bottom of the card and feed the string through to about half of the length of the string.
Tie the card to the top of your stick and push the stick into the ground next to the monstera securely, with the card facing the plant.
Smear the card with either honey, non-stick glue, or Vaseline over the entire length facing the tree and done, one homemade insect trap.
The one issue with this method is that it doesn’t get the wingless thrips, so it is best used as an opening move to dealing with the infestation.
Removing The Thrips With A Damp Cloth Or A Lint Roller
Due to the monstera being so big, this one can be a bit painstaking, but it is worth giving a try.
Since the thrips have mostly infested the leaves of the trees mostly, you go through each leaf and remove them using a damp cloth.
Get a large bowl with a tiny amount of dishwashing soap or regular soap (maybe a quarter of a teaspoon) and mix it with warm water.
Wet the cloth in the water and then wipe the top and the underside of each leaf and any stem you feel is appropriate.
The soap is hard to hold onto and will take away any purchase the bugs might have on the leaf. Once you are done, give the plant a spritz with a hose.
Make sure you are aiming in such a way that water does not fall from the leaf into the soil, as the thrips may survive and return in a week.
Alternatively, you can use a lint roller and roll it over the leaf. The sticky nature of the roller will pick the thrips up easily and will also make sure that none fall into the soil below.
This might be a better method than the cloth, because thrips can survive easily in wet environments, but either is a good option.
Insecticidal Soap
Insecticidal soap is a soap that is not as dangerous to the plant as other soap, but is incredibly dangerous to any very small insect that crosses its path (big ones tend to not be affected).
This method may be a bit of scorched earth for some people’s liking, but it gets the job done, and you may be left with little choice.
Although it does many things to an insect, the main way it kills is through suffocation. When you use this on an insect, it will disrupt their way of breathing.
Arthropods (insects, bugs, spiders, etc.) breath through their skin through anaerobic respiration.
The soap will either block these openings or damage the cells that they breathe through, stopping the insect from being able to breathe.
The effect of insecticidal soap is only effective when it is wet and when it dries, it does nothing.
When you want to use it, either get a ready to use bottle or a concentrate – that you then dilute in water. If you do not have it in a spray bottle, transfer it into one.
Spray a tiny amount on one leaf and leave it for a day. When you come back, if you see brown spots or damage to that area of the leaf, dilute the soap by half or get a more plant friendly insecticidal soap.
If the plant is fine, it is time to start spraying.
Spray the upper and lower side of the leaves, along with the stem, once a day.
Keep doing this everyday, checking for plant damage as you go, for two weeks until you can’t find any more thrips.
Since monstera is a big plant, always water the plant before you begin spraying.
While the spray shouldn’t hurt it, it might do if the plant is in a weakened state. Also, try to use the soap in the early morning or late evening, when it will take longer to dry.
Ladybugs
Many people can name predatory bugs, but did you know that one of the keystone predators of the bug world is the ladybug?
They are crucial to controlling fast-growing and unwanted populations of herbivorous insects. They mainly feed on small soft bodied plant eaters, like mites, aphids, and thrips.
You can buy packets of them from any gardening store or online. You just need to do a couple of things before you release them into your garden.
First, put a damp clean sponge in their container with some food like raisins. They probably haven’t eaten in a while and will need some nourishment before hunting.
Second, try to contain them to the affected plant with a net or sheeting.
This can be removed once most of them have begun hunting on the plant after a few minutes, but it just makes sure they don’t all fly away.
Then you can release them. Ladybugs can eat between 50 and 100 little bugs a day, so the thrips won’t have time to replenish their numbers.
Cuttings
These are the best ways to save a monstera, but sometimes it is too late. If you are in this situation, you can get a new monstera from a cutting of the old one.
Simply, cut one of the least affected or unaffected stems, including the node at the end.
Wash it clean and put it in a jar of room temperature water. Change the water every few days and in a few weeks roots will begin to grow from the plant.
After a month or so, you can plant it in the garden.
Preventative Measures
Sometimes the best way to deal with pests is to stop them in the first place. As such, we have some preventative ways to deal with these nuisances before they become so:
Isolate Any New Plants You Purchase
Thrips can get everywhere, and so exposing your garden to a new plant with potential thrips is not ideal.
Therefore, you should place the plant in an isolated space far away and contained from your other plants for thirty days. If you see no thrips or evidence of thrips in that time, it can join the rest.
Wipe And Clean The Leaves Regularly
Wiping your leaves down isn’t just for getting rid of thrips, but it can prevent them as well.
Dirt can contain eggs and if it gets on your leaves, then you will have an infestation. Therefore, wiping the leaves down weekly can stop this.
Check The Soil
The soil of a plant can show you a lot and contain a lot of nasty creatures.
Removing weeds from the soil and checking to see if there are any insects you don’t want lurking there can help you see whether you need to take action.
Conclusion
Thrips are one of those tenacious creatures that gardeners do battle with every summer.
However, by following the advice in this article, you should have no problem keeping your garden clean and clear for the season.
Hi, my name is Amy Enrich and I have had a keen green thumb since my parents first taught me how to sow a sunflower seed. The process of watching it grow from seed to sprout, sprout to shoot, and then to a full-blown plant is a wonderful sight - I never get bored of it!
I love talking to anyone who will listen about plants, different varieties, how to look after them, and more. That is why I have created Plant Vessel, to help other plant lovers look after their new family members properly and keep them thriving!
Please stick around and enjoy my plant content, and don’t blame me if it influences you to go and buy some more plants!
