Hello! I posted earlier about my Indian banyan tree, but ...
Hello! I posted earlier about my Indian banyan tree, but I can no longer see the post. Anyway, I was recently gifted the tree and have a problem with the leaves developing patchy areas. Eventually the leaves turn yellow and fall off. Looking to diagnose the problem, I’d hate to lose this tree!
7
@PoignantEllisia Omg I think you’re right! I’ve never looked very closely but I just did and saw tiny dark critters. Here is the wiping and another photo. They are teeny tiny and darkish red brown. Almost looks like there is some webbing too and I just witnessed one drop from one leaf to another like a spider lowering itself with webbing. My apologies, I’m a newbie with plants so this is crazy to watch.
This is a long post so I have broken it up into sections so you can jump to treatment if that's what you are looking for:
1. Context (my personal experience before thrips identification)
2. About Thrips
3. Identification
4. Considerations
5. Products
6. My treatment approach/timeline
7. Update on my progress
8. Other helpful tips/prevention/interesting products
1. CONTEXT
To my recollection, my thrips infestation began sometime after the new year, heading into the spring. I had given my Calathea some tap water over the winter because I ran out of water reserve from my dehumidifier. The leaves started getting crispy and dying but there was always new growth. Then the red pigmentation started fading from the backs of the leaves and eventually, there were black inky-like splotches on the backs of the leaves (picture 1). (I thought maybe the colour on the back of the leaves was bleeding. Any way to blame myself! Am I right?)Â
Eventually, a new leaf started growing in crisp, and that's when I knew games were afoot and I took to Reddit. Shout out to the Redditor who eventually helped me identify thrips as the culprit!
I had never dealt with an infestation. Although looking back at some of the plants of yesteryears, I think I likely have had pests take down plants in the past but didn't know any better. Heck, I even thought I may have thrips about a month before the Redditor confirmed my suspicions teaching me the valuable lesson of trusting my instincts (and research) better.
By the time I realized what was going on, they had spread quite significantly and I ultimately had to treat almost all of my plants.
2. ABOUT THRIPS
Thrips spread quite quickly and easily because they are so hard to see/ identify (especially for less experienced plant lovers), and they can fly (albeit not very well). It's likely that by the time you realize what is happening they have spread to at least a few plants.
Thrips lay their eggs in the leaves so topical insecticides won't kill the eggs; Each adult thrips can lay up to 10 eggs a day. And larvae and nymphs can fall into the soil so there could be some lurking in the soil. Thrips have a long life cycle Adult thrips, which can lay eggs, live about 30 days total. Their eggs, untreatable in the leaves without systemic pesticides, hatch in about 3-4 days, live as larvae for 1-4 days, and then as nymphs for 1-3 days, before they become adults. I am not an expert in this area, this is based on my research, and could be slightly inaccurate.
Thrips can also reproduce asexually so it only takes one to start the infestation again. To top it all off, thrips can develop pesticide resistance (more on that in section 4). Even with systemics, I would recommend a focus on physical removal of thrips because of the reasons previously mentioned.
3. IDENTIFICATION
Thrips are super small, and when you see them on your plant vs in photos it's almost impossible to tell. I added a picture of what I saw on my plants (picture 2) VS a zoomed-in photo of what they looked like up close (picture 3). I pulled the thrips off using a lint roller (more on that in section 6).
The nymphs are even smaller and look like specs of black dirt, but on closer inspection, you can see them slowly wiggling (seriously, I looked at a black spec for almost 60 seconds before I concluded it was a nymph because it was wiggling).
The thrips I had were black but they come in other colors and may not look exactly like the ones in my photos.
4. CONSIDERATIONS
Consider the time you are willing to put in.
The approach I took was one of hypervigilance. I am in Canada and can't get systemic pesticides and I spent 2-4 hours every day checking my plants and treating anything I found pests on.
Since thrips can spread easily, have a long life cycle, lay eggs in plant tissue that can't be treated by insecticides available in Canada, and develop pesticide resistance, I decided hypervigilance was the best approach for me. However, because of all of these factors, I do think daily leaf cleanings (more on that in section 6), are still vital even if you use systemic pesticides (I won't be talking about systemics).
I eventually treated every plant in my home, checking every single plant just in case because I didn't want the infestation to start again.
I suggest removing any leaves that look very infected because it's likely thrips laid eggs in them; they will grow back! And throw away any plants you feel you aren't fully committed to. This took me a while to accept. But I had a few plants that had been looking bad for the past year that I was rehabilitating, I realized it wasn't worth the effort when I had an infestation on my hands.
5. PRODUCTS
a) Safer's Insecticidal soap
- This product only kills thrips on contact and won't kill any eggs in the leaves.
- As I mentioned, I am in Canada and we cannot purchase systemic pesticide
b) Food-grade Diatomaceous Earth
The verdict is out on whether this works, but I thought it was worth a shot.
You apply it to the soil and it potentially dries up any nymphs that end up in the soil. It only works when it's in its powdered form, once it becomes damp, it won't be effective, if it is at all.
Keep in mind this is dangerous to inhale so use a mask when working with it, and keep it away from kids and pets.
If you have nowhere to put your plants safely away from kids and pets, DO NOT USE IT (look it up, it's not safe or worth the risk)
6. MY TREATMENT APPROACH/TIMELINE
Day 1
- I rinsed every plant in the shower or outside with a sprayer (hose or shower head) to dislodge as many thrips as possible.
- Next, I sprayed down each leaf THOROUGHLY with insecticidal soap. I used a makeup brush to apply the product on larger plants and leaves and to get into stalks of plants
- I added diatomaceous earth to the soil after I made sure my plant was already adequately hydrated. If the soil is too damp, the diatomaceous earth will absorb moisture and won't be effective anymore
Weeks 1-2
- When I first realized I had a thrips infestation, I decided to treat the plants more frequently with insecticidal soap than the package recommended (it recommended reapplying every 2 weeks).
- I repeated spraying with insecticidal soap 2X per week for the first two weeks. This could kill some plants, but I made peace with the fact that the plants were already being killed and would die without intervention.
- I also reapplied diatomaceous earth after every watering.
Week 3
- I reduced to treating the plants once a week OR if I saw a thrips (adult nymph or larva) on a plant.
- I made this decision at week 3 because I was no longer seeing adult thrips, just nymphs/larva
Weeks 1-5
- I kept my infected plants in 2 quarantine zones, I have enough space but if you don't it's okay!
Zone 1 is where I keep plants that I found thrips on recently
Zone 2 is where I keep plants that I found thrips on, but haven't found one on in a while (I just used my personal judgment for zone 2)
Throughout all of that, I used a clean damp paper towel or lint roller on sturdier plant leaves (looking at you monstera) to wipe down every single plant leaf, every single freaking day.
You could possibly reduce it to every other day or every 2-3 days if needed (eggs hatch in about 4 days). I used the daily leaf cleanings as a way to monitor the infestation and to physically eliminate thrips. It's okay to throw away plants or take cuttings of healthy leaves and start again to reduce your treatment efforts. But, if you let the thrips mature, they start laying more eggs only prolonging the infestation and increasing the chance of resistance to your pesticide of choice; I can't recall if thrips can become resistant to insecticidal soap. You want to catch and remove them at the nymph phase so they can't multiply and prolong the infestation.
- Because I was a noob and the thrips went undetected for weeks/months, I did clean every plants leaves weekly in my home as a way to monitor my other plants and detect if the thrips had spread so I could move other plants to quarantine if necessary. Thrips can develop pesticide resistance so diligence is key to getting rid of them.
It was a nightmare and took me 2-4 hours each day, I got seriously burnt out, which is why I suggest considering the time you are willing to put in. It's okay to throw away plants and start again, or take cuttings of healthy leaves!
I also kept a tracker for all of my plants so I could record when I last saw a thrips and on which plant. I also tracked when I wiped the leaves of each plant (even though it was daily) vs when I applied insecticidal soap. I have about 25 plants so it made it easier to keep track of everything.
Week 6 onwards
I continued to wipe every plant's leaves twice per week to make sure there are no more thrips since eggs hatch in 3-4 days, it's perfect timing for me to catch and remove larvae if there are any.
Eventually I reduced this to once per month as a means of ongoing pest prevention and early detection.
That's literally what I did. Put in the time. And I became seriously burnt out after 3 weeks.
7. UPDATE ON MY PROGRESS
I first started treating the thrips on July 13th. Unfortunately, I didn't realize that some plants had them, so it caused me to find more thrips on other plants after having gone 4 days without spotting anything from July 19-22; I only spotted nymphs luckily. But, that's when I decided to just bite the bullet and treat everything. B
As of August 13th, I've gone 19 days without seeing a thrips(larvae, nymph, or adult) on a plant. I am still checking and wiping the leaves every week or less and I just removed my plants from quarantine on August 11th.
I will continue to wipe the leaves once per week until the end of August. After that point, I will go into prevention mode (things I learned from all of my research).
8. OTHER HELPFUL TIPS/PREVENTION/INTERESTING PRODUCTS
I have learned that prevention is key. Now that I have done a lot more research, and from this experience, I will be checking and wiping leaves down approximately monthly to prevent pests.
I know some people use a neem oil spray to apply to leaves as a preventative measure as well, but I have never done that.
Also, something many of us have heard over and over, but a warning which I never heeded until now, is to quarantine your new plants to ensure they are healthy and don't have pests that can spread to your existing plants.
I recently went to a plant shop that recommended some other products that I find interesting and may be able to assist in preventing pests. I can't attest to their effectiveness just yet, but it's worth looking into. I just started using them myself.
Bios herbal pesticides (Canadian-based company, I am not affiliated)
I see this as a more long-term solution to pest prevention (similar to neem how people can use neem oil spray).
I intend to use this monthly now that the infestation is gone. It contains white willow bark, and other beneficial natural ingredients, which apparently help make plants more resilient. You can apparently also use aspirin as it is also derived from white willow bark.
Check out more details here: https://www.youtube.com/watch?v=ZQB4rJjsX5E
Bios Natural Fertilizer (Canadian-based company, I am not affiliated)
Again, I can't attest to its effectiveness but I just started using it myself. I just applied it for the second month and plants seem to be growing well, however, it's also peak summer when plants grow the best and I have never used any sort or fertilizer so I can't compare the product to other fertilizers. I just know that I was always scared to use fertilizer for fear of burning my plant's leaves.
A lot of Canadian weed producers are using similar live soil products their crops. It does contain nitrogen, phosphorus, and potassium, their website contains confirmation of the amounts that were confirmed by the University of Guelph.
It also contains microbes and beneficial bacteria to help fungi and beneficial bacteria thrive. The fungi feed on things in the soil and then generate natural fertilizer for your plants to use. Apparently, it helps plants be more resilient and fungi and microbes exist in soil naturally so it's intending to recreate that environment.
I know this is very long! But, I hope my experience can help someone.
1. Context (my personal experience before thrips identification)
2. About Thrips
3. Identification
4. Considerations
5. Products
6. My treatment approach/timeline
7. Update on my progress
8. Other helpful tips/prevention/interesting products
1. CONTEXT
To my recollection, my thrips infestation began sometime after the new year, heading into the spring. I had given my Calathea some tap water over the winter because I ran out of water reserve from my dehumidifier. The leaves started getting crispy and dying but there was always new growth. Then the red pigmentation started fading from the backs of the leaves and eventually, there were black inky-like splotches on the backs of the leaves (picture 1). (I thought maybe the colour on the back of the leaves was bleeding. Any way to blame myself! Am I right?)Â
Eventually, a new leaf started growing in crisp, and that's when I knew games were afoot and I took to Reddit. Shout out to the Redditor who eventually helped me identify thrips as the culprit!
I had never dealt with an infestation. Although looking back at some of the plants of yesteryears, I think I likely have had pests take down plants in the past but didn't know any better. Heck, I even thought I may have thrips about a month before the Redditor confirmed my suspicions teaching me the valuable lesson of trusting my instincts (and research) better.
By the time I realized what was going on, they had spread quite significantly and I ultimately had to treat almost all of my plants.
2. ABOUT THRIPS
Thrips spread quite quickly and easily because they are so hard to see/ identify (especially for less experienced plant lovers), and they can fly (albeit not very well). It's likely that by the time you realize what is happening they have spread to at least a few plants.
Thrips lay their eggs in the leaves so topical insecticides won't kill the eggs; Each adult thrips can lay up to 10 eggs a day. And larvae and nymphs can fall into the soil so there could be some lurking in the soil. Thrips have a long life cycle Adult thrips, which can lay eggs, live about 30 days total. Their eggs, untreatable in the leaves without systemic pesticides, hatch in about 3-4 days, live as larvae for 1-4 days, and then as nymphs for 1-3 days, before they become adults. I am not an expert in this area, this is based on my research, and could be slightly inaccurate.
Thrips can also reproduce asexually so it only takes one to start the infestation again. To top it all off, thrips can develop pesticide resistance (more on that in section 4). Even with systemics, I would recommend a focus on physical removal of thrips because of the reasons previously mentioned.
3. IDENTIFICATION
Thrips are super small, and when you see them on your plant vs in photos it's almost impossible to tell. I added a picture of what I saw on my plants (picture 2) VS a zoomed-in photo of what they looked like up close (picture 3). I pulled the thrips off using a lint roller (more on that in section 6).
The nymphs are even smaller and look like specs of black dirt, but on closer inspection, you can see them slowly wiggling (seriously, I looked at a black spec for almost 60 seconds before I concluded it was a nymph because it was wiggling).
The thrips I had were black but they come in other colors and may not look exactly like the ones in my photos.
4. CONSIDERATIONS
Consider the time you are willing to put in.
The approach I took was one of hypervigilance. I am in Canada and can't get systemic pesticides and I spent 2-4 hours every day checking my plants and treating anything I found pests on.
Since thrips can spread easily, have a long life cycle, lay eggs in plant tissue that can't be treated by insecticides available in Canada, and develop pesticide resistance, I decided hypervigilance was the best approach for me. However, because of all of these factors, I do think daily leaf cleanings (more on that in section 6), are still vital even if you use systemic pesticides (I won't be talking about systemics).
I eventually treated every plant in my home, checking every single plant just in case because I didn't want the infestation to start again.
I suggest removing any leaves that look very infected because it's likely thrips laid eggs in them; they will grow back! And throw away any plants you feel you aren't fully committed to. This took me a while to accept. But I had a few plants that had been looking bad for the past year that I was rehabilitating, I realized it wasn't worth the effort when I had an infestation on my hands.
5. PRODUCTS
a) Safer's Insecticidal soap
- This product only kills thrips on contact and won't kill any eggs in the leaves.
- As I mentioned, I am in Canada and we cannot purchase systemic pesticide
b) Food-grade Diatomaceous Earth
The verdict is out on whether this works, but I thought it was worth a shot.
You apply it to the soil and it potentially dries up any nymphs that end up in the soil. It only works when it's in its powdered form, once it becomes damp, it won't be effective, if it is at all.
Keep in mind this is dangerous to inhale so use a mask when working with it, and keep it away from kids and pets.
If you have nowhere to put your plants safely away from kids and pets, DO NOT USE IT (look it up, it's not safe or worth the risk)
6. MY TREATMENT APPROACH/TIMELINE
Day 1
- I rinsed every plant in the shower or outside with a sprayer (hose or shower head) to dislodge as many thrips as possible.
- Next, I sprayed down each leaf THOROUGHLY with insecticidal soap. I used a makeup brush to apply the product on larger plants and leaves and to get into stalks of plants
- I added diatomaceous earth to the soil after I made sure my plant was already adequately hydrated. If the soil is too damp, the diatomaceous earth will absorb moisture and won't be effective anymore
Weeks 1-2
- When I first realized I had a thrips infestation, I decided to treat the plants more frequently with insecticidal soap than the package recommended (it recommended reapplying every 2 weeks).
- I repeated spraying with insecticidal soap 2X per week for the first two weeks. This could kill some plants, but I made peace with the fact that the plants were already being killed and would die without intervention.
- I also reapplied diatomaceous earth after every watering.
Week 3
- I reduced to treating the plants once a week OR if I saw a thrips (adult nymph or larva) on a plant.
- I made this decision at week 3 because I was no longer seeing adult thrips, just nymphs/larva
Weeks 1-5
- I kept my infected plants in 2 quarantine zones, I have enough space but if you don't it's okay!
Zone 1 is where I keep plants that I found thrips on recently
Zone 2 is where I keep plants that I found thrips on, but haven't found one on in a while (I just used my personal judgment for zone 2)
Throughout all of that, I used a clean damp paper towel or lint roller on sturdier plant leaves (looking at you monstera) to wipe down every single plant leaf, every single freaking day.
You could possibly reduce it to every other day or every 2-3 days if needed (eggs hatch in about 4 days). I used the daily leaf cleanings as a way to monitor the infestation and to physically eliminate thrips. It's okay to throw away plants or take cuttings of healthy leaves and start again to reduce your treatment efforts. But, if you let the thrips mature, they start laying more eggs only prolonging the infestation and increasing the chance of resistance to your pesticide of choice; I can't recall if thrips can become resistant to insecticidal soap. You want to catch and remove them at the nymph phase so they can't multiply and prolong the infestation.
- Because I was a noob and the thrips went undetected for weeks/months, I did clean every plants leaves weekly in my home as a way to monitor my other plants and detect if the thrips had spread so I could move other plants to quarantine if necessary. Thrips can develop pesticide resistance so diligence is key to getting rid of them.
It was a nightmare and took me 2-4 hours each day, I got seriously burnt out, which is why I suggest considering the time you are willing to put in. It's okay to throw away plants and start again, or take cuttings of healthy leaves!
I also kept a tracker for all of my plants so I could record when I last saw a thrips and on which plant. I also tracked when I wiped the leaves of each plant (even though it was daily) vs when I applied insecticidal soap. I have about 25 plants so it made it easier to keep track of everything.
Week 6 onwards
I continued to wipe every plant's leaves twice per week to make sure there are no more thrips since eggs hatch in 3-4 days, it's perfect timing for me to catch and remove larvae if there are any.
Eventually I reduced this to once per month as a means of ongoing pest prevention and early detection.
That's literally what I did. Put in the time. And I became seriously burnt out after 3 weeks.
7. UPDATE ON MY PROGRESS
I first started treating the thrips on July 13th. Unfortunately, I didn't realize that some plants had them, so it caused me to find more thrips on other plants after having gone 4 days without spotting anything from July 19-22; I only spotted nymphs luckily. But, that's when I decided to just bite the bullet and treat everything. B
As of August 13th, I've gone 19 days without seeing a thrips(larvae, nymph, or adult) on a plant. I am still checking and wiping the leaves every week or less and I just removed my plants from quarantine on August 11th.
I will continue to wipe the leaves once per week until the end of August. After that point, I will go into prevention mode (things I learned from all of my research).
8. OTHER HELPFUL TIPS/PREVENTION/INTERESTING PRODUCTS
I have learned that prevention is key. Now that I have done a lot more research, and from this experience, I will be checking and wiping leaves down approximately monthly to prevent pests.
I know some people use a neem oil spray to apply to leaves as a preventative measure as well, but I have never done that.
Also, something many of us have heard over and over, but a warning which I never heeded until now, is to quarantine your new plants to ensure they are healthy and don't have pests that can spread to your existing plants.
I recently went to a plant shop that recommended some other products that I find interesting and may be able to assist in preventing pests. I can't attest to their effectiveness just yet, but it's worth looking into. I just started using them myself.
Bios herbal pesticides (Canadian-based company, I am not affiliated)
I see this as a more long-term solution to pest prevention (similar to neem how people can use neem oil spray).
I intend to use this monthly now that the infestation is gone. It contains white willow bark, and other beneficial natural ingredients, which apparently help make plants more resilient. You can apparently also use aspirin as it is also derived from white willow bark.
Check out more details here: https://www.youtube.com/watch?v=ZQB4rJjsX5E
Bios Natural Fertilizer (Canadian-based company, I am not affiliated)
Again, I can't attest to its effectiveness but I just started using it myself. I just applied it for the second month and plants seem to be growing well, however, it's also peak summer when plants grow the best and I have never used any sort or fertilizer so I can't compare the product to other fertilizers. I just know that I was always scared to use fertilizer for fear of burning my plant's leaves.
A lot of Canadian weed producers are using similar live soil products their crops. It does contain nitrogen, phosphorus, and potassium, their website contains confirmation of the amounts that were confirmed by the University of Guelph.
It also contains microbes and beneficial bacteria to help fungi and beneficial bacteria thrive. The fungi feed on things in the soil and then generate natural fertilizer for your plants to use. Apparently, it helps plants be more resilient and fungi and microbes exist in soil naturally so it's intending to recreate that environment.
I know this is very long! But, I hope my experience can help someone.