Angel Trumpet (Brugmansia)/Frost Protection

Question from Natalie:
I live in Texas, and our winters are not that cold. I have an angel trumpet planted in the ground. What can I do to keep the plant from dying if and when we have a freeze? Thanks.

Answer from Pat:
There are several things you can do to keep your angel trumpet (Brugmansia) from being frost bitten or killed on cold nights. The first is to taper off on fertilizing in late September. Feeding tropicals later than September encourages soft fresh growth with is more easily harmed by frost. Additionally water less in fall to help harden off the plant, but don’t allow ground to be dry on frosty nights. This might seem contradictory, but by not watering as much in fall you help the plant to slow down in growth. On the other hand, dry ground is known to increase frost-damage on plants, whereas those with moisture around their roots withstand frost better.

Another thing to do is always listen to weather forecasts and be aware when frost is expected. If the plant is in a pot pull it under eaves, so long as the eaves are not in a patio with walls all around it. As I have written in my book, “Frost builds up inside walled patios like water in a swimming pool.”

When frost is expected, cover the plant with an old sheet. This is usually enough to protect plants from frost. But remove the sheet first thing in the morning before sun hits the plant. And don’t throw away those old outdoor Christmas tree lights with incandescent bulbs. These can be hooked up to electricity, draped on bamboo poles next to plants or even over the plants so the warmth can keep off frost. Special frost-protecting fabric, available at some nurseries, can also be draped over plants with the lights underneath but not touching.