Thoroughly Water plants if it's not going to rain before the freezing temperatures arrive. It may sound illogical. However, a moist ground stays warmer than dry soil. Watering the night before the freeze comes will insulate the root structure of the grass and plants and decreases the potential for cold injury.
Avoid watering when temperatures are below 40°F or when sustained freezing temperatures are expected within 24 hours as this water will freeze and not be available to the plants.
Cover Plants – Protect plants from all but the hardest freeze (28°F for five hours) by covering them with sheets, towels, blankets, cardboard or a tarp. You can also invert baskets, coolers or any container with a solid bottom over plants. Cover plants before dark to trap warmer air.
Cold weather prep for plants in winter
Drought-stressed plants are more susceptible to cold damage, so watering plants a few days in advance of a cold snap is beneficial. Watering just before the freeze can help too by creating warmth, and the water loses its heat slowly over the hours into the colder temperatures.
The idea of using irrigation to help prevent frost is that the water that is sprayed in the fields freezes and releases heat to the air as the liquid water changes to ice. The goal is to keep the air temperature in the area at 32 F by adding heat in this process.
Keep outsides valve open so water remaining in the pipe can expand without causing a break. When freezing weather is coming, turn off water to outside spigots and drain all water from the line.
Wind down the water as temperatures begin to drop below 40 degrees. Most summer annual plants will freeze and die with the first or second hard frost. As always, irrigate your perennials and annuals in the morning when you can! That way, the soil has time to soak it all in before temperatures drop in the evening.
The cold can mix badly with water, so just make sure the night time watering happens when temperatures are warmer. Late Spring, Summer and early Fall / Autumn generally have warmer months and this tends to mean overnight temperatures are warmer too.
Morning watering is actually preferable to evening watering as the plant has time to dry before the sun goes down. At night, water tends to rest in the soil, around the roots, and on the foliage, which encourages rot, fungal growth, and insects.
Know Your Plants' Cold Tolerance
Some frost-tender plants need to be covered as soon as the temperature hits 32°F, while others can handle lower temperatures and/or longer freezing periods. You'll need to look up each of your plants to verify its cold tolerance.
When Should You Cover Plants? Cover your plants at night and remove them during the day when the temperatures rise above 32 degrees F, so that the soil can warm up again. Some outdoor plants won't survive the harsh conditions of winter, bring them inside and use these tips for caring for them through winter.
Throughout the winter your plant is still going to need some water. If the soil gets completely dry, the plant can die of desiccation. While regular watering isn't necessary, monitor the moisture level and water if the soil is dry.
Water for Plants During Winter
As a rule of thumb, water when the soil is dry to the touch, the temperature is not below 40 degrees F. (4 C.) and, if possible, when the wind isn't blowing. Drying winds may carry off much of the water you're trying to apply to the roots of your beloved plants.
Light freeze - 29° to 32° Fahrenheit will kill tender plants. Moderate freeze - 25° to 28° Fahrenheit is widely destructive to most vegetation. Severe or hard freeze - 25° Fahrenheit and colder causes heavy damage to most plants.
Most of the houseplants we grow originated in the tropics or sub-tropics where rainfall is relatively warm. Ice cold water will cause root shock, which may lead to permanent root damage, leaf drop and other problems. Allow the water to warm to room temperature before watering the plants.
If it stays cold for more than one night, can I keep my plants covered, or should I remove the coverings at some point? A. Our recommendation would be to remove the cold protection covering once temperatures are above 32 degrees.
Creating Watering Schedules for Winter Gardening
Try watering at mid-day — when temperatures are higher—so it can soak in before it freezes at night. Water your landscape once or twice per month from November to April. New roots form in the months of March and April. It is most critical to water during these months.
When To Winterize Your Gardens. The best time to start winterizing gardens is after the first hard freeze in the fall. A hard freeze occurs when the temperature gets below freezing overnight, killing off tender annual plants and vegetables.
With adequate rainfall, established plant species appropriate for our climate typically need little to no supplemental irrigation during the winter. Exceptions to this rule include newly planted trees and shrubs, plants in containers, and periods of unusually dry winter weather.
The smaller streaks are from condensate coming off falling water droplets — not water that has frozen midair. The air is not quite cold enough to freeze water immediately, which happens at about minus-42 degrees, Terry said.
Water freezes at 0 degrees Celsius and 32 degrees Fahrenheit. The freezing point is the temperature by which a liquid turns into a solid. When liquid water freezes, internal energy is removed from the system.
How to Freeze Water Bottles? I would recommend letting an inch or two of water out first before resealing the bottle and placing it in the freezer. This would ensure there is enough room for expansion during freezing without worrying the lid will pop off!