This is the first year I tried container gardening. I have hyacinth that are 3 inches tall in 4 inch clay pots. Also tulips, crocus and hyacinth in as large as 12 clay pots. Last night I was too tired to throw a blanket over the pots. This morning I woke up and some of the pots were FROZEN SOLID. After months of TLC--everything was looking SO good--have I damaged or killed my bulbs? Anne PS: Global TV said temps would drop to -4 or -5 last night.
First off... where are you? I assume you are in the Vancouver area, which did have a few degrees of frost last night. Depending on where in the Lower Mainland you are, the range was between -5C and 0C. The most recent Environment Canada forecast I've seen for Monday night is -1C. These cold temperatures are nothing more than radiative heat loss (the open, cloudless sky drawing heat away from warmer bodies at the ground). The air mass around us is not really that cold; however, even gentle winds will accelerate heat and moisture loss at these temperatures. Plants in pots are always more vulnerable to the cold and drying-out than those in the ground, but these temperatures should not be a problem for anything except completely open flowers (bulbous plants are generally very well-adapted to spring temperature fluctuations). I would not be worried unless we were to sustain sub-zero temperatures for a number of days. Nevertheless, you can protect your pots when it's cold by merely placing them under cover, so that they're "shaded" and don't lose heat to the atmosphere, or by placing them on bare soil, where they receive heat conducted from the ground. And make sure your plants are not too dry, as droughty conditions will make them more vulnerable to both cold and desiccation when they are growing.
Defrosted THANKS DOUGLAS!! Interesting comments. I live in Kitsilano. Everything seems OK since my initial shock. I've watered some of the containers and a wool blanket over the pots at night keeps them from freezing. Perhaps you could help be with another question. In the early winter I planted nine hyacinth bulbs [Splendid Cornelias] in a plastic container. They were definitely getting crowded so I've replanted them in an old wine crate. But I didn't have the heart to break the root mass apart and space the bulbs more generously in the crate. Should I go ahead and separate the bulbs--which means breaking apart some of the root mass--and replanting them. Once the bulbs start to flower they will definitely 'appreciate' the space. Kind regards - Anne
Lift and separate bulbs only after the foliage has died down completely. That way, you don't risk damaging growing tissues. The bulbs should perform well, in spite of the crowding, as long as the soil is relatively fertile.
