Scheduling of gardening chores is as important now as it ever was. We plant warm season vegetables and annuals in time for spring and summer. We plant cool season vegetables and annuals for autumn and winter. We pick flowers as they bloom. We harvest fruits and vegetables as they ripen. We watch the seasons change on our calendars, as well as in the locally specific weather.
Yet, the one scheduling tool that we do not hear as much about as we did when agriculture was more common in the region is the ‘last frost date’. It refers to the average date of the last potentially damaging frost for a specific region. The last of such frosts might actually be earlier or later, but the last frost date remains a standardized time to plan particular procedures and planting around.
There are likely a few reasons why we do not talk about the last frost date much. The most relevant reason is likely the timing. Around here, the last frost date is sometime in January. It is earlier in some spots, and later in others, but it is sometime between January 1 and 30. It is simply too early to limit much of what we do in the garden in early spring, and is irrelevant to most winter chores.
It might seem to be just as irrelevant now, since the last frost was so long ago. Seed for warm season vegetables and annuals is sown as the weather gets warmer only because it would grow too slowly while the weather is too cool in winter, not because of a threat of frost. There really is quite a bit of time between the last frost and warm spring weather, while the weather is still rather cool.
However, pruning of plants that were damaged by frost should have been delayed at least until after the last frost date, and perhaps as late as spring. Although unsightly, damaged growth shelters inner growth from subsequent frost. Besides, premature pruning stimulates new growth that is more sensitive to subsequent frost. Most of such pruning is delayed until just after the last frost date.
If delayed longer, fresh new growth will show how far back damaged stems must get pruned.