A: Hydrangea buds, flowers and leaves all contain a chemical called amygdalin. It is broken down in several ways to produce a small amount of cyanide. If you’ve heard that raw almonds, apple seeds and peach pits are poisonous, it’s because they contain amygdalin. It is broken down in one’s stomach to make tiny amounts of poison. In theory, the heat from your fire pit should destroy the amygdalin in the hydrangea wood. However, I make a practice of never describing something as “safe” or that the smoke is not harmful. I recommend that you discard the wood.
Q: I’ve read your website advice about applying preemergent. You say apply in March when the soil temperature at 2 inches deep is 55 degrees and rising. Where we live, the soil at that depth is already above 55 degrees but I don’t know if we’re “rising.” I’m tempted to put preemergent on even though it’s late January! James Walsh, Johns Creek