Hi All, I've been having a lot of problems with spider mites (red mites) underneath the leaves of my roses. They are really tough pests and giving a lot of damages to my roses, many leaves becoming yellow and dry and the plants are not growing well. At first, I used "Imidacloprid" but it didn't work. Worse, these days, I've read some articles on the net about "Imidacloprid" causing increasing population of spider mites. Is it correct? I've also tried "Abamectin" 2 times (5 days apart). Everytime, I applied very very thoroughly and wetting every single leaves, both upper and lower surfaces. It seemed to reduce the numbers but didn't completely remove them. I've also put some small water trays beneath my rose plants but didn't work, too. My roses plants receive strong hot sunlight for about 6 hours and I know this will encourage mites but it's also the only way to encourage flowering in my roses, right? So, please help me what to do next. I'm really frustrated with this mites.
make sure that you are using a miticide for the spider mites rather than an insecticide, the products arent the same necessarily.
Mites sure are nasty to control. Abamectin is a widely used Miticide generally producing good results. You mention that you have applied Abamectin two times with minimal results. Abamectin does have slight contact control but is mainly systemic. This might lead one to believe that your mixture is a bit strong? Thus slightly killing on contact but not getting proper absorption into plant tissue for systemic effects. It is just a thought, but you might try mixing slightly below label rates and mix with a horticultural oil to aid in foliage coverage and penetration. If I remember correctly you mentioned in a prior post that you were gardening on a balcony. I am not sure if you are just dealing with a few Rose plants or a lot. If you had just a few plants and wanted to control Mites you could purchase a small bottle of Lime Sulphur, mix a squirt bottle at half label rates for fruit tree spraying (or even as low as 1%) and apply a light mist, directly on contact, near the end of the sun each day to burn off the adults. Also Mites do not like wind, an oscillating fan will slow down populations, along with wiping down the leaves with just water. Please be careful, you seem to have some pretty harmful chemicals. Abamectin and Imidacloprid are reasonably toxic to humans and can mess with your nervous system if absorbed by skin or breathed in. Mites will also host on many other plants that may not be as visual or damaging as they are on your Roses. Cedars can host Mites too. Good Luck! Jim.
I would also look into other plant hosts to your Mites... and stop using dangerous chemicals, unless you care not for your own health.... but seriously, I would shower and or irrigate the foliage for a trial period with soapy water and a drop of vegetable oil.... continue this until the mites are decimated... however your local sounds subtropical? Heat and moisture are mites best friend!
I have used potassium based soap (e.g. Laters) with some success. You have to apply it before the sun gets up on the leaves with a fine mist sprayer. Spider mites hate damp conditions. Bob
