Don't keep the coverings on your plants for more than two days in a row without removing them in the day since this can cause water to become trapped underneath, leading to fungal diseases and can cause plants to produce new growth that can be easily damaged by cold.
Yes, that's right: plants provide all the “air” they need for their own survival. They're perfectly happy sealed in a plastic bag. How long can you keep your plants sealed up like this? Easily 6 months, quite possibly up to a year.
-Don't make the mistake of thinking that a plant can remain covered for a few days when the weather calls for more than one night of frost. The protection needs to be taken off every morning when the sun comes out. Plants can't breathe under a heavy container, a layer of plastic or fabric.
(If freezing temperatures are predicted for several consecutive nights, it's safe to leave your plants covered for up to a week. Some of your neighbors, however, may not be happy about this.) Small old fashion electric Christmas lights hung or placed near the base of the plant (heat rises) will add warmth to a plant.
Never cover a plant with just plastic, however, as the plastic will damage the plant. Make sure that a cloth barrier is between the plastic and the plant. Be sure to remove the sheets and blanket and plastic first thing in the morning after an overnight cold snap.
In soil, plastics have the potential to cause problems at the chemical level. Like a magnetic attraction, contaminants can bind to plastics, resulting in toxic accumulation. Contaminants can also hitch a free ride on plastics and potentially make their way into 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.
All plants will be fine for 7 – 10 days and can cope with having a good watering before you leave. It's only after about 10 days you need to make sure most of them have more water.
I did some research and found out that houseplants need to be taken indoors before overnight temperatures dip below 45 degrees. Most tropical plants suffer harm from temperatures below 40 degrees.
Plants in the ground
In fact, you can leave plants covered with blankets or sheets for several days without harming them if freezes are likely for several nights in a row. But eventually the covers must be removed so the plants can get light.
One obvious sign of dead floras is mushy and fragile stems plus roots. Once a plant has reached this stage, no home remedies will save it.
Place gallon jugs or jars of water (size dependent on how long you expect to be gone) alongside your plant with a piece of twine or yarn in the water, and the other end around the soil of the plant. The water will wick from the jug to the plant and keep it's soil moist while you are gone.
Plastic will transmit cold air to the plants, causing more harm than good. We recommend using cotton fabric or frost cloth to protect plants from frost.
Wrapping the bottom two rungs or steps of the tomato cage with plastic wrap simulates a greenhouse. The heat is trapped inside the plastic wrap and the plants are blocked from the wind. By the time the plants reach the top of the plastic wrap, they're strong plants and well adjusted to the temperatures and wind!
Plants under plastic bags retain moisture and even capture what the plants produce by transpiration.
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.
Semi-hardy cool-season crops (beets, carrots, Swiss chard, lettuce, cauliflower, potatoes, parsley) grow in minimum daytime temperatures of 40 degrees and higher. They cannot withstand hard frost without some kind of covering or protection.
For many plants, temperatures below 50°F can cause problems. Adjust thermostats to cater to your comfort, but remember your plants need some consideration. Avoid placing plants near cold drafts or heat sources. Keep plants several inches away from exterior windows.
If you have a manageable number of plants, you can buy a water-recycling terrarium or DIY one with a large clear plastic bag and keep them happy for months. Put the open bag on a waterproof floor in a room that will stay at a moderate temperature (cool in summer, warm in winter) and out of direct sun.
The best type of frost protection is frost cloth, which is a breathable fabric because it can 'breathe,' you can leave the frost cloth on your plants for a longer period. But, use it only when there is a threat of frost. After three days, uncover your plants during the day to allow the sun to reach your plants.
Move plants to a shady area
Plants in direct sunlight will dry out faster than those in indirect sunlight, so whenever I leave for vacation, I move anything that's by a window to a less sunnier area.
Plastic bags are non-biodegradable in nature. It remains in the soil for a long period of time without getting decomposed. It prevents seeping of water into the soil and thus prevents the growth of plants. Thus, plastic bags pollute the soil and are considered bad for the soil.
Transport of Plastic in Root Tissue. The uptake of MPs and NPs in plants has been detected and plastic particles are especially absorbed on root hairs.
The plastics that are already used for food storage tend to also be safe to garden with. Like its older cousin, HDPE, LDPE plastic is very safe in a wide range of temperatures and can even be used in the microwave. You're likely to find LDPE in your garden in the hoses you use to water.