Any part of a plant may be affected by cold damage. In spring, it's usually tender growth, which will appear watersoaked and may turn black. Flower buds can sustain damage during winter dormancy or during the blooming period. Plants will either have reduced numbers of blooms, and hence fruit set, or won't bloom at all. In fall, if plants aren't hardened off, they can sustain cold injury in temperatures well above those tolerated by acclimated plants. Root injury is rare unless plants are in raised beds or containers. Generally younger plants are more susceptible than mature plants. Cold injury on woody plants usually presents in the form of frost cracks in wood or bark. Mature leaves may turn red, purple, brown or black and may or may not fall off the tree or shrub.
Keep plants watered. Hydrated plants can be more tolerant of low temperatures and moist soils have a higher heat capacity than dry ones. Avoid fertilizing/pruning in late summer/early fall so as not to stimulate new growth. Move containers to protected areas during threat of frost. Cover raised beds with row covers. Mulch around the bases of trees, especially young ones. Prevent defoliation by insects/disease to maximize food storage and improve winter hardiness. If plants have already sustained cold injury, wait to prune until you know the extent of the damage. Many plants can grow new foliage after dieback.
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