Answer: If three are doing well and one is not, then there may be something different about its location (also, some varieties are simply touchier than others). Perhaps it is faced with competing tree roots or the drainage pattern or sun pattern is slightly different? Watering is always a judgement call. You need to keep the soil moist but not sopping wet. The best way to tell is to use your finger and check the soil about an inch down. A few inches of organic mulch will help moderate the soil temperature and keep it moister longer. Clematis are sensitive to soil temperature, so using a mulch to shade the roots is a good idea. In the meantime, trim away any discolored portions, and be very patient. Clematis will often come back from the roots.
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