Answer: Caryopteris in general are quite problem free plants, however they do require a full sun location in soil that is well drained, meaning not soggy. (Once established, they are considered to be very drought tolerant.) Yellowing of the lower leaves can certainly be a symptom of overwatering. If you planted them in a heavy clay soil that stays waterlogged, planted them in a low spot that is extra damp after rain, or planted them deeper than they grew originally, you might be seeing the results of a root problem due to excess moisture. If you think any of the above would apply, you might try transplanting them to a more suitable location. I hope this helps you trouble shoot.
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