Florida is known for its sunny and tropical weather, however, on occasion, when the winter months creep up, the temperature can drop to freezing or below. Florida residents may not be equipped with the necessary knowledge to protect their plants, so we wanted to share a few things to consider when a Florida freeze does hit. It is important for plants to survive the frigid weather.
The first question to ask is do the plants need to be protected from a frost or a freeze? Although they may sound like synonyms, there are different steps to take depending on the answer. The event is considered frost when ice forms on the surface of plants. A freeze is when the moisture within the plants freeze. A frost advisory is issued when the temperature is expected to fall to 36 degrees F or lower, and a freeze advisory is issued when the temperature is expected to fall to 32 degrees F or lower. A “hard freeze” occurs when the temperature falls to 28 degrees F or below.
One very common practice used to protect plants during a freeze is to cover them with a sheet or blanket. This is only effective for a light freeze or frost. By covering the plants, they stay insulated. The warm air from the ground stays trapped around the plant, protecting it from a brief cold snap. Take it a step further by adding plastic to the covering. Be sure to wrap the plastic on the outside of the sheets, as plastic alone will damage the plant. It is important for the plant to receive adequate ventilation and sunlight so it is not damaged. Also be sure the cover is removed during the daytime.
Another measure that can be taken to keep plants warm and insulated is to add a significant layer of mulch around the plants above the roots. This method protects the roots by keeping them warm even if the rest of the plant freezes.
Another preventative step would be to water landscape plants well prior to a freeze. This method encourages plants to absorb more radiation from the sun that will be released at night, keeping the plants warm and allowing them to retain heat.
If a freeze advisory is in place, ornamental plants can be protected by sprinkling them with water from the time freezing temperature begin until the water begins to thaw. This maintains a constant temperature of 32 degrees F on the leaves.
Palm trees are most often difficult to protect during cold snaps. To attempt to keep them warm, string lights can be wrapped around the trunk and throughout the fronds. Although this method may just seem like a festive decoration, these lights provide warmth to the tree to help it survive. Additional lights such as flood lights can be angled towards the fronds, further providing warmth and heat to the tree. Just as with other plants, sheets and blankets are effective insulators for plants warmth, and can be tied or weighed down after covering the palm tree.
Above all, it is important to remember certain plants freeze at different temperatures. Plants protect themselves from freezing in different ways, some plants produce hormones, some lose their foliage and so on. Plants adapt to survive in different ways, just because one component of the plant cannot survive a freeze, for example, the leaves, it does not mean other parts of the plant cannot. Plants have something called a hardiness rating, which essentially explains where a plant grows well and what temperatures it can withstand. Before planting, consider referring to a Hardiness Zone map to see what plants can thrive in the area.