Chilli thrips

[cpp gardener]

I am the head rosarian (by default) of a semi-public rose garden with 1000+ bushes in inland southern California. For several years we have been dealing with chilli thrips with only moderate success, we've lost several bushes and even whole varieties (5 of each variety). Typically the first flush of growth and blooms is good and when the temps go up so do the thrips. The bushes' response is dropping leaves and then the stems sunburn, beginning a downward spiral. I'm now determined to bring them under control and return our garden to its former glory!
Has anyone had much success getting these under control? The size of the garden precludes using home remedies ( including baking soda, vinegar, milk and what have you) or waiting for predators to control them. I know that the original infestation was in Florida and spread west from there so I'm hoping someone in that area has had good results with something. The garden is surrounded with a wide assortment of other hosts so I realize that whatever we use will have to be re-applied during the season, I'm just looking for something that will slow the little monsters down so the bushes will have a chance to recover a little.
Any help is greatly appreciated!

 

[Sheal]

That's a lot of roses to look after! My first thought would be to try Neem Oil, a natural product.

 

[Chuck]

Here in Texas Chilli thrips are a fairly new and serious problem. Different types of nematodes have been tried with very limited success. Most insecticides are also of limited effectiveness. However, good results have been seen using a two pronged approach by first using Neem in the spring and followed up by a spray regime of spinosad