You can get rid of spider mites on your Fushia plant by either spraying it with a very diluted amount of Murphy oil soap and water. And you can also bring them in and give them a cold shower it will kill the mites.
Mites can be very picky indeed. So the best way to get rid of them is using a type of insect repellent. This is the only effective thing that will work to get rid of the mites from the fushia plant. Therefore, I recommend that you use raid to get rid of them.
This sounds odd, but spraying the plant with a diluted amount of Murphy oil soap and water will work. Also try bleach and water sprayed on. You can also give them a cold shower with just plain water.
Simply put bleach and water in a bottle and spray directly on the fushia plant to get rid of spider mites. There are also spider sprays to keep spiders off plants. Some sprays can be bought at stores for a cheap amount. Use sprays with the directions on the bottle.
Any of a dozen or more insect anf fungal sprays are available in your local hardware store or outdoor center. The usual course of action is to spray all leaves, both on the top and the bottom surfaces. You should repeat this at least twice weekly until under control. Repeat once weekly.