Spinosad or Bt?

TerrapinBlazin

TerrapinBlazin

Well-Known Member
It’s getting to be the time of year when pests move into the outdoor garden. Last year my outdoor crop got ravaged by caterpillars and this year I want to prevent them with something natural and non-toxic, and from what I can tell that’s either spinosad or Bt. I haven’t had any problems with anything other than caterpillars, so technically Bt would suffice, but I’m intrigued by spinosad. Apparently it stays active on the leaves longer and is completely nontoxic to both humans and dogs. I’ve also read it can be used in the plant systemically to get rid of thrips and mites, which could come in handy indoors.

The thing that has me wondering if it’s all pointless though is if spraying it on before the buds start really developing will be good enough. Last year the caterpillars really attacked in late August and early September and the buds were way too developed to spray.

I don’t know what species of caterpillar ravaged my buds last year, and I don’t know if it came in from the ground or the adult moth uses cannabis as a host plant. If eggs are hatching on the plant then it seems like the spray would work better because I can get them earlier, but I don’t want to spray anything on well developed buds, even bacteria or fermented bacteria juice. I’ve gotta get this figured out quick though. I lost entire sections of colas last year.
 
Joedank

Joedank

Well-Known Member
TerrapinBlazin said:
It’s getting to be the time of year when pests move into the outdoor garden. Last year my outdoor crop got ravaged by caterpillars and this year I want to prevent them with something natural and non-toxic, and from what I can tell that’s either spinosad or Bt. I haven’t had any problems with anything other than caterpillars, so technically Bt would suffice, but I’m intrigued by spinosad. Apparently it stays active on the leaves longer and is completely nontoxic to both humans and dogs. I’ve also read it can be used in the plant systemically to get rid of thrips and mites, which could come in handy indoors.

The thing that has me wondering if it’s all pointless though is if spraying it on before the buds start really developing will be good enough. Last year the caterpillars really attacked in late August and early September and the buds were way too developed to spray.

I don’t know what species of caterpillar ravaged my buds last year, and I don’t know if it came in from the ground or the adult moth uses cannabis as a host plant. If eggs are hatching on the plant then it seems like the spray would work better because I can get them earlier, but I don’t want to spray anything on well developed buds, even bacteria or fermented bacteria juice. I’ve gotta get this figured out quick though. I lost entire sections of colas last year.
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I have used both and Spinosad works best for caterpillars. BT is great on borers and soil based pests IME
 
TerrapinBlazin

TerrapinBlazin

Well-Known Member
I’ll probably go with the spinosad because it seems both more versatile and durable. Good to know it’s most effective on caterpillars. How late into flowering can you realistically apply it?
 
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TerrapinBlazin

TerrapinBlazin

Well-Known Member
That’s a good call. I do have a tree near my plants. Any idea how it works on fungus gnats? They always end up in my flower tent. I don’t overwater but it’s all relative here in the desert. I don’t think any more will get in now that I put prefilters in all my tent intakes, but I’d love to wipe out any remaining larvae. A brightly colored fly trap did work well to get rid of most of them.
 
Joedank

Joedank

Well-Known Member
TerrapinBlazin said:
I’ll probably go with the spinosad because it seems both more versatile and durable. Good to know it’s most effective on caterpillars. How late into flowering can you realistically apply it?
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I like to give it a few weeks to metabolize before harvest. But the bottle says 2 days yikes!
 
TerrapinBlazin

TerrapinBlazin

Well-Known Member
Joedank said:
I like to give it a few weeks to metabolize before harvest. But the bottle says 2 days yikes!
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Wow. If you can spray it on buds two weeks before harvest (let alone two days) that’s awesome. Those caterpillars don’t stand a chance this year :)

Also what’s the deal with neem oil? Been reading about that stuff for years, including that it’s the likely culprit for cannabis related hyperemesis (puking your guts out constantly and only being able to relieve it with hot baths).
 
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See green

See green

Well-Known Member
The moths lay their eggs on the buds and leaves. They are usually orange or brownish. I usually use spinosad one week and alternate with BT as needed. The key is to start spraying before flowers form. I feel safe using spray till about half way through flower if needed. After that its physical inspection and picking off eggs and worms.
 
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Joedank

Joedank

Well-Known Member
TerrapinBlazin said:
Wow. If you can spray it on buds two weeks before harvest (let alone two days) that’s awesome. Those caterpillars don’t stand a chance this year :)

Also what’s the deal with neem oil? Been reading about that stuff for years, including that it’s the likely culprit for cannabis related hyperemesis (puking your guts out constantly and only being able to relieve it with hot baths).
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I use neem weekly up to point where you see flower clusters form . Week 2 indoors then I stop
 
AquaTerra

AquaTerra

Well-Known Member
BTK would be for caterpillars BTI would be for fungus gnat larvae but still have to get the flies. Sponosad works for lots of bugs but proper IPM is a must other wise you'll get spinosad resistant species.
 
DCcan

DCcan

Well-Known Member
Israelensis strain (BTi) - Bonide Mosquito Beater WSP
Israelensis strain (BTi) - Gardens Alive Knock Out Gnats Granules (fungus gnat larvae control)
Israelensis strain (BTi) - Gnatrol (fungus gnat larvae control)
Israelensis strain (BTi) - Summit Mosquito Bits
Israelensis strain (BTi) - Summit Mosquito Dunks
Kurstaki strain (BTk) - Bonide Bacillus thuringiensis
Kurstaki strain (BTk) - Bonide Thuringiegsis (BT) Concentrate
Kurstaki strain (BTk) - Ferti-lome Dipel Dust
Kurstaki strain (BTk) - Hi Yield Thuricide Concentrate
Kurstaki strain (BTk) - Safer Brand Caterpillar Killer
Kurstaki strain (BTk) - Safer Garden Dust w/Bt
 
TerrapinBlazin

TerrapinBlazin

Well-Known Member
Nice. The fungus gnats haven’t been around since it got really hot out. I’ll be treating for them once it cools off.
 
TerrapinBlazin

TerrapinBlazin

Well-Known Member
See green said:
The moths lay their eggs on the buds and leaves. They are usually orange or brownish. I usually use spinosad one week and alternate with BT as needed. The key is to start spraying before flowers form. I feel safe using spray till about half way through flower if needed. After that its physical inspection and picking off eggs and worms.
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This is super helpful. Thanks! So at least some do use cannabis as a host plant. I wish cannabis attracted beneficials. If it was swallowtails munching leaves I wouldn’t give a single fuck. They were all over my parsley last year but left the weed completely alone.
 
Nizza

Nizza

Well-Known Member
TerrapinBlazin said:
That’s a good call. I do have a tree near my plants. Any idea how it works on fungus gnats? They always end up in my flower tent. I don’t overwater but it’s all relative here in the desert. I don’t think any more will get in now that I put prefilters in all my tent intakes, but I’d love to wipe out any remaining larvae. A brightly colored fly trap did work well to get rid of most of them.
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Are you re using soil? It could be the decaying roots or something, if that’s the case look into using pond-zyme to break the roots down fast

that’s what I will be using for my coco coir
 
TerrapinBlazin

TerrapinBlazin

Well-Known Member
I’m sure it’s decaying roots because I recycle my soil. The way my rotation is set up lets the soil compost for close to a month before it gets reused but I’d imagine that doesn’t completely break down every root. I also inoculate my soil with mycorrhizae and trichoderma harzanium, which I’m sure the fungus gnats love.
 
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