Answer: Plumerias are tender to frost, so if the temperatures get down to freezing, protect them by moving to a garage or shed until the weather warms. The plants won't do well in cold, wet soils, and should be kept on the dry side during the winter months. This may mean that your plumeria will have to be moved to a protected place out of winter rains, or planted in very fast draining soil in a raised bed.
Soft growth may indicate that it's immature growth, or it may indicate the growing conditions are less than ideal. If your plants are in containers, move them to an area where they won't get rained upon. This might be against the house, under the eaves, or on a bright but protected porch. Don't fertilize until new growth begins in the spring; then water regularly during periods of active growth, reducing the amount of water during the autumn and winter months.
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