Canola seedlings can with stand a considerable frost (-5 to -8 0 C) if plants have become acclimatized following a few days of cold temperatures. However, canola seedlings growing under warm conditions will be tender, and can be killed by even a f few degrees frost. Ice crystals will form on the leaf surface before they form within cells causing damage.
Prior to taking any action, wait four to five days to assess any damage.
Check the growing point for green colour at the centre of the leaf rosettes. Although the cotyledons or other leaves may be black, re-growth can occur in 4-10 days depending on weather conditions.
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