Answer: Some plants, especially shrubs and trees, may not grow much the first year they are planted. Instead they direct their energy to establishing a good root sytem first. With a hydrangea, however, I would have expected some growth in the course of an entire summer. (If it was just planted in August, I would not expect much growth however. A flush of new growth now would not have time to harden before winter so it is just as well.) Heat and drought may have simply slowed it down or if there is possibly a root problem. If the soil is insufficiently prepared the roots may grow around and around in just the original potting soil rather than reaching outward into the ground and this can cause stunting. The only way to see if this is true is to dig it up (carefully and gently, starting at some distance in case the roots have spread out!). The leaves may be yellowing because it is fall, or they may be reflecting a soil problem, or they may indicate an insect or disease problem. For a more specific diagnosis you might want to take a sample to your County Extension (837-1402) -- they might also help with some soil analysis if you suspect that is a problem.
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