Here are a few cold weather garden tips. Learn more from Boxerwood's January Garden Notes at our website.
Weather Warnings: Hasn’t this weather been unbelievable? I am nervous about some of the plants. We live in USDA Plant Hardiness Zone 6B (although I think it is getting closer to 7). The low end of that zone is 0 to -5, with zone 7’s being 0 to 5 degrees. Our Crape Myrtles are only root hardy here. If your Crape Myrtle doesn’t start to leaf out in late spring, you may have to cut it back drastically. Crapes leaf out late so give it a chance before whacking away at it. At home we wrap some of our new dwarf evergreens with burlap in the winter. The cold wind can be very damaging to evergreens. Plants transpire water through their leaves, so evergreens continue to loose water during the winter. When the ground is frozen or dry, the plants are not getting the moisture they need and start to draw water from living cells. If too much water is given off, the cells die, the leaves turn brown and the plant dies. Winds accelerate that moisture loss, especially if the plant has been planted in a sunny open area with no protection. The following suggestions for protecting plants from the cold come from the North Carolina Extension:
1. Plant varieties that are hardy to your area. I have to confess I sometimes bend this suggestion a bit. I might try a zone 7 plant, iffy out in the county where I live. Partly, that is the plant collector in me, always trying something new, but there are a few protected microclimates near our house where it stays a little warmer.
2. Try to locate less hardy plants in the highest part of the yard, as cold air tends to settle in the lower areas.
3. Add an extra layer of mulch in the fall to help preserve moisture
4. Try to shade more tender plants from direct winter sun. Here is where a burlap wrapping helps.
5. Don’t feed quickly available nitrogen to your plants in the fall, encouraging new growth. You want growth in the spring and summer, not in the fall where it might be susceptible to early frosts.
Heavy wet snow can also be a problem. Remember March of 2013? The heavy wet snow caused more damage here at Boxerwood than the derecho. We are still clearing up brush from that storm. It is a good idea after a storm, to brush the snow off of arching evergreens, small trees, shrubs, and woody plants that have a very dense twig structure, such as Japanese Maples to prevent breakage.