Are you asking about mixing them or about applying them on alternate days or which to apply first? Mixing them is not recommended as they can neutralize each other but research shows they can be applied in alternating weekly applications and still have beneficial effects. You spray the copper first, let it dry and work, then the following week you spray with the Spinosad.

Dave

Thanks. My concern this year rainy weather. Alternating would make spraying each every 2 weeks. I would think it is too seldom for both to retain any protective properties during rainy periods.

Normally the label instructions call for weekly applications so that is the normal pattern. However the labels also usually say something about applying again after heavy rains so you would have to do that as well but still in an alternating pattern.

It depends in part on exactly what you are using them to prevent/treat and what plant you are using them on. For example, if you know you already have a bacterial disease on tomatoes and are using the copper for it then what pest is on the tomatoes for the Spinosad and the Bt?

In other words both products are not often needed for the same plant at the same time. And if they are then you may need to switch to a different product or a different approach? It becomes a matter of priorities. Say I had a tomato plant with both a bacterial disease and horn worms or stink bugs. I'd use the copper spray and hand pick the pests or use DE for them.

Dave

there's no reason to spray bt and spinosad together....whatever spinosad kills includes whatever bt kills.

Thank you, randy. I alternate them too.

Dave, thank you for explanations.

I started to see feeding activity on Tom and Peppers. No signs of bacterial disease yet. But with all the rain and wounds created from feeding...I guess I should start with Bt/Spinosad to prevent wounds first. After 7 days hit with Copper to prevent bacterial infections. And then if see signs of feeding repeat Bt/Sp in 5 days.

Found this on one of the European sites

"...

Copper should preferably not be used together with acidifying agents or phosphorous agents.

Do not mix with biological insecticides containing Bacillus thuringiensis spp or any other fungal or bacterial biological agents. Can be applied 5 days before and 7 days after the application of most biological agents in a spraying programme."

My understanding though that disease gets into the plant through the wounds from bug's feeding.

so confusing

No. Some bugs can transmit diseases, like thrips, but your more common diseases are air and soil born, infecting the foliage. That's why I'd start with the copper.

Dave, feel free to let us know if I'm giving misinformation here, but that's how my understanding of it is.

I think you are confusing bacterial diseases with fungal diseases. I use Daconil for fungal and Phosphoric Acid too.

Copper - for bacterial. I don't like copper for fungal. I don't like copper in general.

Bacterial are not only the ones that are transmitted by bugs. Bacteria in general get into plants through wounds, not only from feeding but from pruning and wind damage too. and then through seeds.

And copper is only used for specific bacterial dis on Tom and Peppers.

Are there actual bugs you are trying to treat? Preventative fungicide/antibacterial is often recommended, but preventative spraying for bugs isn't.

Sure, as I mentioned earlier I see signs of feeding on my peppers and tomatoes.

holes and poop. Caterpillars.

i would find the caterpillars and check them for wasp eggs before spraying. they may be carrying their own end on their backs.

tigrikt - yes the quote from the European source is pretty much straight manufacturer's recommendation.
"Can (copper) be applied 5 days before and 7 days after the application of most biological agents in a spraying programme."

So just as I said above and carriehelene added, copper first, then the biologicals is the normal approach. But it also depends on exactly what sort of eating activity you are seeing and how much damage. Is the damage severe and do you know for sure that Spinosad will control it? Is there no other method (other than spraying a pesticide) that can control it? That would let you spray the copper first.

For example, my pest issue right now is grasshoppers and stink bugs. Spinosad will sort of kill them - eventually - but meanwhile they will do more damage so I just hand pick them and dust with DE for much faster results. That way I can keep using the copper spray regularly.

Plus do keep in mind that copper sprays are also used and recommended by many for fungal diseases. They were the most common fungicide long before Daconil came along. :) Both fungal and bacterial diseases can be airborne and soil borne as well as due to injuries to the plants. Insect vectors can also transmit a couple of the bacterial diseases but are primarily the viral diseases. Insect Vectored Pathogens in Garden Diseases

So if you feel your pest problem is the most serious go for it but if not then begin with the copper would be my recommendation if for no other reason than the bacterial disease appear to be running rampant this year.

Hope this helps.

Dave

Randy, I do check how the caterpillars look like and if they are infected. But they are fairly small now, I think they are cabbage worms, and they are not infected by parasitic wasps. Unfortunately.

From Cornell web site on Peppers

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A chemical control program is recommended for susceptible varieties that show symptoms, and should begin in the early stages of disease development. Examine the plants every week. It is worthwhile to remove infected plants if they are found early, before there has been the opportunity for spread. If infected plants are found while scouting, apply bactericides (copper fungicides are toxic to bacteria) on a 7 to 10-day schedule; use the shorter interval when rain, high humidity and warm temperatures occur. Stretch the interval by one day for each night that temperatures fall below 61oF. Recent research on Long Island showed that a program where applications began after disease symptoms occurred, was less expensive and worked as well as weekly preventive sprays initiated early in the season before the disease was present. Connecticut growers have used weekly scouting and this "wait-and-see" policy before implementing a spray program with good results for many years. Adding maneb to a copper application has been shown be more effective than using copper alone in some experiments. Efficacy is improved because more copper is dissolved when copper and maneb are agitated together in the spray tank for about 90 minutes before application. However, maneb may not improve efficacy of newer copper formulations that provide more available copper in the spray solution than older products. A high pressure airblast sprayer should not be used because it can disperse the bacteria through a field. Discontinue spraying in late summer when night temperatures are consistently below 61oF and daytime relative humidity is well below 85%. While chemical control can be effective, it is not foolproof. Failure can occur when conditions are very favorable for disease development and when plants are infected with a bacterial strain that is resistant to copper."

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So they recommend to wait for signs of disease

From Cornell

- bacterial speck, tomatoes

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(5) Practice a preventive copper + mancozeb spray program (see Cornell Recommendations for Commercial Vegetable Production for specifics) from anthesis until the first-formed fruit are 1/3 their final size. After that point, the greatest risk of bacterial speck is passed; copper can be dropped from the program, and the full labeled rate of fungicide should be used to control foliar blights, especially early blight.

From Cornell

- bacterial spot, tomatoes

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4) Spray plants with streptomycin before transplanting. After transplanting, apply a mixture of mancozeb plus copper before the occurrence of disease. Protection is most needed during early flowering and fruit setting periods.

So, I am ditching copper till I see an infected Pepper.

Early floweringg and fruit setting of tomatoes are done already.