Answer: Pruning will encourage new growth so I'd go ahead and prune out all the obviously dead plant material and then reduce the healthy parts of the plant by a few inches. New growth should appear in a few weeks. You can feed with an acidified fertilizer (Miracid, Miracle Gro, etc.) after you've pruned. You might want to do a little investigation into why the plants are not thriving. Winter weather can be the culprit, but cultural conditions might also be at work. Make sure you are providing adequate water, but that the soil is also draining well (overly wet soils can suffocate roots and cause branches and stem death). Hope you determine just what the cause might be so you can correct the situation and help your gardenias regain their health.
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