Answer: Spider mites are easier to discourage than they are to control. These pests like dry, dusty conditions so simply hosing your plants off twice a week should keep them at bay. They can spread to other nearby plants so hose those off periodically as well. The simplest approach to control is spray the foliage thoroughly with a garden hose or spray bottle. Special sprays (miticides) can also be purchased, but hose washing is simpler and quite effective. Once you've controlled the spider mites, you should see fewer yellowing leaves. Gardenias are evergreen so it is natural for them to drop their oldest leaves in favor of producing new leaves at the branch tips. This eventually turns into a leggy plant with only puffs of foliage at the branch tips. To keep this from happening, periodically prune each stem back by a few inches. This will encourage more branching and a fuller plant.
Best wishes with your gardenia!
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