Plastic plant pots and propagators are cheap, light, easy to handle and available, and they have advantages and disadvantages compared with other materials. Choose pots according to size, drainage capacity and the purpose for which you want to use them. Most plastic propagators are unheated, but there are heated ones as well - you need to examine these before you purchase.
Plastic and other materials
Plant pots may be made of plastic, terracotta, clay or pot, and they come in different sizes for different purposes. Plastic pots are cheap to buy, but their durability depends upon their thickness. The small ones in which you purchase plants from garden centres are made of thin plastic and are easily breakable. However, there are thicker plastic pots that will last longer. Some very large pots are made of very durable plastic, suitable for long-term planting in gardens or conservatories.
Terracotta, compared to plastic, looks good, but is easily breakable. Like clay, it is porous, and will draw water from the ground and also lets it out. Pot is heavy and if you are dealing with a large vessel, it is hard to move. It is very fragile. Plastic is not the best in appearance, but it is useful and light.
Drainage and size
When purchasing a plastic plant pot, decide what you want to use it for. If it is a large pot for an indoor plant, check that there are drainage holes at the bottom. Indoor plants do not need drainage holes, but outdoor plants do,as heavy rains will drown plants in undrained pots. For planting and potting, have a variety of different plastic pot sizes available to you. Plastic provides cheap pots for routine gardening purposes
Plastic propagators are very common. They come in various sizes, some of them being small enough to fit on a window ledge, and many are of a size that easily fits on a greenhouse bench. These propagators will consist of a plastic seed tray and a transparent plastic lid big enough for there to be room for plants to grow. The better quality lids have ventilators in them to allow plants to respire. However, the plant trays can be used without the lids in some cases.
There are heated plastic propagators. If you are purchasing one of these, check that the plastic is sturdy, as the heat can distort it if it is overused. Even a thick plastic one can be distorted if the heat from the heating element, which is a mat placed under the seed tray, is heated too long, so check out the quality before you buy any pot.