We just received this email (April 10) from Alessandro Ferzoco of Boston:
I uncovered my trees yesterday here in Boston. When the crocuses come up, the forsythia buds turn yellow, and you see robins, it’s time to uncover the trees here. I noticed some mold starting to grow, due to the higher temperatures and the rain we’ve been having but for the most part my trees were in great shape. Last year’s method of covering was far less successful than this year’s. I’m quite happy with my improvements to my method. Last year I had a lot of mold and die back on the trees. I uncovered them earlier than this year (about April 1st), yet I had essentially suffocated them by overprotecting them. The problem was too much of the covering was touching the branches and that there was not enough room for some cold air to enter the covering. I had mistakenly mounded up soil around the base of the tree to really seal down the tarp. The trees did come back, but most of the branches died back to the main trunk and we had a late season of figs here because the trees had to essentially start from very little.
This season I filled paper yard waste bags with leaves to make a sort of building blocks for insulation. After tightly tying the branches together to make the tree as compact as possible, I surrounded it with these packed leaf bags. It was good to have small cracks between the bags for air circulation — it’s not so much the cold as it is the wind that kills fig trees from what my mentors tell me. I put a stake in the middle of this wall of leaf bags, next to the main trunk of the tree, and then draped moving quilts over the top, careful to try to avoid touching the branches of the fig trees as best as possible. I then loosely covered the trees with a tarp to keep them dry, but so that cold air could circulate around the bottom of tree through some small cracks in the leaf bags. It’s important that the moving quilts don’t touch the ground, because if water starts to pool in the spring they will act like a sponge and end up pulling water up across the entire covering, causing lots of mold. The main objective was to avoid totally sealing in the tree. I checked them throughout the winter by pulling back the tarps to make sure that the branches were still looking healthy.
I should note that I wait to thin out branches until the spring to ensure that plenty of healthy branches survive the winter. Our low temperature here was 9 degrees this winter, although night time temperatures between 10 and 15 degrees were also not uncommon during February and March.
Grazie mille, Alessandro!