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Spider mite on mini rose

I had a very severe infestation of  spider mites  on my miniature rosebush. One day I just noticed the plant was totally covered in webs and tiny bugs. I mean, it was really really bad. All of the leaves were turning brown or covered in brown spots. I put it in the shower and sprayed down the plant with a medium pressure spray. This removed all the webs and a lot of the spider mites. Of course it also removed about half of the leaved from the plant, mostly the more damaged ones. A few days later I noticed that there were still a noticeable amount of mites tormenting my plant. I filled a small wastebasket with water and added a few tablespoons of 3% hydrogen peroxide. I submerged the entire plant and soaked it for a few hours in there but I’m not really sure how much that helped, since most arachnids can live up to 24 hours underwater. A few days later there were still signs of the mites eating my plant so I took to mechanical means of removal. I spent about an hour repeatedly flicking the stems with my fingers over a piece of paper and squishing anything I saw moving on the paper. Over time less and less mites were coming off, and I took that as a sign that I had eradicated most of them. I wanted to be sure that they were all gone, so I filled a small cup with 3% hydrogen peroxide straight from the bottle, and individually dipped the remaining leaves in it for a few seconds. This was a pretty easy task because there were only a few clusters of leaves left.  After that I sprayed the plant with water to wash away the peroxide and let the plant dry. This whole time my boyfriend (who gave me the plant) was laughing at how much effort I was putting in to saving this little plant that looked like it was about to die anyway. But during the next few days, with the mites completely exterminated, new leaf buds started appearing all over the plant where the leaves had been falling off throughout the infestation.  My plant is now re-growing its leaves and starting to look really healthy again.

I know this is a very long story but I know these mini rosebushes are very prone to spider mite infestations so I wanted to share my success and method in treating a very severe infestation. If I had let it go another day before showering it off, it probably would have died, as there were thousands of the little suckers all over my plant.

 Don’t give up on your plants! Dana

Thrips are tiny, narrow insects with feathery wings which are difficult to detect.  The adult female will lay eggs on the leaf surface. Once they hatch they suck the juices out of flowers and new leaf shoots. One generation of thrips will live about two weeks and continue to multiply thru the season producing several generations. To test your plant for thrips shake and infested flower head over a piece of white paper and you should see dark fecal pellets and white dead plant tissue Another way to monitor for thrips is to hang blue-colored sticky traps by the plant. Yellow traps will also work. The sooner you spot and treat the easier they will be under control.

Thrips attack dry, stressed plants.  They will feed on leaves which will be flecked white and have black specks on the underside of the leaves. Their favorite targets are light-colored flowers such as white, blue and yellow. Infested flowers will become discolored and disfigured and the buds will turn brown, dry up and die.   Damage can look similar to spider mites infestation. The added bonus is that they can transmit viral disease.

Other than disfiguring the plant, thrips should not kill a healthy plant. The best way to approach this problem is to remove the infested flowers/buds and spray with insecticidal soap twice a week for 2 weeks until  they are under control.  Since they like dry conditions keep the plant moist not dry. A garlic spray can also be effective in repellilng thrips.  Mix 1/2 cup of finely chopped garlic in 1 pt of water, strain and spray every few days for 2 weeks. Persistance pays.

 A spray that contains spinosad (Conserve) is a biologically, safe organic insect killer which you can apply directly on the flowers and leaf buds. It works by contact and by injestion and will not harm most beneficial insects or predatory mites.  Neem (botanical) will also work.
A systemic such as Orthene will give you long term control. Orthene is not environmentally friendly since it will kill all insects even beneficial ones. Extreme caution should be used during application.

Plants affected by thrips: tuberous begonia, dahlia,daylily, gladiolus, hollyhock, iris, peony, rose.