A warning: Spinetoram does not seem to be effective against mealies
Posted: Tue Feb 14, 2023 5:52 am
A quick background: I have two "sets" of insecticide. One is my outdoors insecticide, which I purchase from an agricultural supply store. The stuff from the Ag store is waaay cheaper than the stuff I can buy at the hardware store. For example, 200 g/L permethrin in a 200ml bottle is about $15 at the hardware store, but 650 g/L permethrin in a 1L bottle is about $30. So you are getting 4x the volume at ~3x the concentration, or 12x as much insecticide. So it's a no-brainer to buy it from the Ag store.
Except for one thing: most ag store insecticides use kerosene (paraffin in the US?) or something similar as a solvent, which stinks. So while I use the ag store stuff in my grow cabinet in the shed and on my outside plants, for my other grow cabinet in the house (my indoors stuff)I pay the extra money for the hardware store stuff, which is normally dissolved in some less smelly solvent (if it smells at all).
This is where the tale begins.
About half-way through winter (June-July) I spotted a Gymnocalycium mihanovichii at a garden centre with some nice patterning and lots of hairs. It was a good price so I brought it home. It was about to flower despite the season and I had another Gymno in my indoors grow cabinet that was also about to flower, so I hoped to cross breed them. Except, after a few weeks the flower buds died. The cactus then started to look a bit sad, looking dehydrated and then going from vibrant green and black, to a tan and brown colour.
Then I noticed a mealy bug on my single Eulychnia acida seedling in the grow cabinet. I was more than a little peeved as I had gone through a lot of searching to get a hold of one. I then looked through the rest of the plants in the cabinet and found the little bastards were everywhere. The G mihanovichii in particular had tonnes of them hiding in the hairs of the plant
I didn't have any inside permethrin left, so I went to the hardware store intending to buy some more. On the shelf next to the permethrin was Yates "Success Ultra", which is spinetoram. It was about 50% more expensive than the permethrin, but it was advertised as making 40 L of insecticide solution vs 10 L for the permethrin for the same sized bottle, so I figured I'd give it a shot.
That was a mistake.
The spinetoram seemed to kill all the mealies, but a few weeks later I spotted a few more. So I gave another application and then to be sure I gave a second a few days later. This seemed to have done a better job, but about two months later I spotted some more. This time I doubled the concentration and tried again - and nope, still there.
During this I spent a lot of time wondering if I'd just accidentally kept bringing it in from outside, so I was extra careful not to bring things inside for a while. With the next appearance, having had lots of success soil-soaking for fungal problems, I decided to soak all the plants in the cabinet. This seemed to work for about 2 months.
So a month or two back, I decided to put of with my hallway smelling of kerosene for a few days and soil soaked everything in my outdoors permethrin. I think this has worked, mostly because the G mihanovichii started to regain its colour.
Yesterday, now that it doesn't look like its on the verge of death, I repotted it. On the roots there were a lot of those little fluffy white nests that mealies make. I do mean a lot: almost the whole taproot was covered in them. I poked around and didn't see any evidence of live mealies, but just to be sure I dipped the plant in permethrin solution. Then, based on suspicion, I unpotted several other plants and found that they too had mealies all through the roots.
So anyway, spinetoram seems to be kind of garbage. Even going off label with the concentration it barely works, nor does submerging the nests in the stuff.
Anyone else had a similar experience?
Except for one thing: most ag store insecticides use kerosene (paraffin in the US?) or something similar as a solvent, which stinks. So while I use the ag store stuff in my grow cabinet in the shed and on my outside plants, for my other grow cabinet in the house (my indoors stuff)I pay the extra money for the hardware store stuff, which is normally dissolved in some less smelly solvent (if it smells at all).
This is where the tale begins.
About half-way through winter (June-July) I spotted a Gymnocalycium mihanovichii at a garden centre with some nice patterning and lots of hairs. It was a good price so I brought it home. It was about to flower despite the season and I had another Gymno in my indoors grow cabinet that was also about to flower, so I hoped to cross breed them. Except, after a few weeks the flower buds died. The cactus then started to look a bit sad, looking dehydrated and then going from vibrant green and black, to a tan and brown colour.
Then I noticed a mealy bug on my single Eulychnia acida seedling in the grow cabinet. I was more than a little peeved as I had gone through a lot of searching to get a hold of one. I then looked through the rest of the plants in the cabinet and found the little bastards were everywhere. The G mihanovichii in particular had tonnes of them hiding in the hairs of the plant
I didn't have any inside permethrin left, so I went to the hardware store intending to buy some more. On the shelf next to the permethrin was Yates "Success Ultra", which is spinetoram. It was about 50% more expensive than the permethrin, but it was advertised as making 40 L of insecticide solution vs 10 L for the permethrin for the same sized bottle, so I figured I'd give it a shot.
That was a mistake.
The spinetoram seemed to kill all the mealies, but a few weeks later I spotted a few more. So I gave another application and then to be sure I gave a second a few days later. This seemed to have done a better job, but about two months later I spotted some more. This time I doubled the concentration and tried again - and nope, still there.
During this I spent a lot of time wondering if I'd just accidentally kept bringing it in from outside, so I was extra careful not to bring things inside for a while. With the next appearance, having had lots of success soil-soaking for fungal problems, I decided to soak all the plants in the cabinet. This seemed to work for about 2 months.
So a month or two back, I decided to put of with my hallway smelling of kerosene for a few days and soil soaked everything in my outdoors permethrin. I think this has worked, mostly because the G mihanovichii started to regain its colour.
Yesterday, now that it doesn't look like its on the verge of death, I repotted it. On the roots there were a lot of those little fluffy white nests that mealies make. I do mean a lot: almost the whole taproot was covered in them. I poked around and didn't see any evidence of live mealies, but just to be sure I dipped the plant in permethrin solution. Then, based on suspicion, I unpotted several other plants and found that they too had mealies all through the roots.
So anyway, spinetoram seems to be kind of garbage. Even going off label with the concentration it barely works, nor does submerging the nests in the stuff.
Anyone else had a similar experience?