I have a thing for glass cloches. Bell-shaped and graceful, cloches range in size from tiny to large. These glass covers are both beautiful and practical. Useful for protecting seedlings at the beginning of the season, or as a coldframe for keeping frost at bay at the end of the season they also can provide a lovely setting off houseplants.
Inside they are perfect for creating terrariums. All you need is a plate the cloche can sit on or a bowl the cloche can fit inside of to make a terrarium that will make even the most pedestrian of greenery look stylish and artful. Many cloches will come with a base as well.
Outside, the cloche can serve as a small greenhouse, protecting plants from frost and even snow. While you can use glass cloches outside, there are also wonderful plastic cloches that even have ventilation, which makes it easier not to cook your plants, which can happen surprisingly fast with a closed cloche.
You can also make your own cloche, by using mason jars or even the glass orbs of discarded light fixtures - often easily found at second hand stores or yard sales. Gallon milk jugs and plastic soda bottles can also be easily transformed into cloches by cutting off the bottoms and then either poking holes in the tops, or leaving the tops off entirely for more ventilation.
One warning is that in direct sun, on any cloche--glass or plastic--can heat up very quickly and to high temperatures, even if the air is cold, which can easily cook your plants. To avoid this, either remove the cloches in the morning or elevate them off the soil, so that cool air can circulate.
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