I've also been using neem products to lower the thrip numbers. Two things I'd add to your helpful comment. Using a non-petroleum dish soap like castile soap is more environmentally friendly and not using a neem oil product when it's over 80 degrees or it can potentially burn blooms and leaves. Additionally, I've been using neem cake in the soil to mess with thrip reproduction and I seemed to have good results last year. We'll see how this year goes.

Thanh, please keep us posted on how your treatment is going.

Towanda,

What is 'neem cake'?

Moses

Towandaaz, Please tell us about neem cake.

This is what I've purchased: https://www.amazon.com/Neem-Cake-Fertilizer-100-Organic/dp/B00GUC0N1I/ref=sr_1_3?ie=UTF8&qid=1525718214&sr=8-3&keywords=neem+cake 

Last year when I had what felt like an out of control thrip(s) infestation, I begin doing some research and found some - what I believe to be good - academic research regarding neem cake applied to soil for its ability to mess with thrips in their mating stage. (I may have bookmarked the research, but I'm on vacation and returning later this week. I'm happy to look for it then.) The other cool thing is that neem is a mild fertilizer and shouldn't harm the plant.

It made sense to me to use neem oil spray (the real cold pressed stuff diluted which is what I think Thanh is using) for thrips on leaves and buds when the temp is cool - but after the thrips drop down into the soil to mate - then what?? So I thought this neem cake research was interesting as part of a two-pronged attack. Because I live in such a dry climate, I soak the neem cake (2-3 cups) in a netted bag in a very large bucket and soak the soil around the rose with it (most of my roses are potted). I also break the neem up after the soak and scratch it into the soil or sometimes just use it dry. I can't remember if this "tea" was described in the research or if it said to just scratch it into the soil. I'll have to look when I get home.

It seemed to reduce the thrips population last year but I don't truly know if something else like weather or something else cut the numbers down. I'm trying the neem methods again this year because it's organic and is supposed to only harm the "sucking" bugs.

I hope this helps and if anyone has more to add regarding neem products, that would terrific.

Thank you Towandaaz. I will look into the neem cake. I am a believer now :))