A growbag is a planter filled with a growing medium and used for growing plants, usually tomatoes or other salad crops. Originally made of plastic, modern bags are also made from jute or fabric. The growing medium is usually based on a soilless organic material such as peat, coir, composted green waste, composted bark or composted wood chips, or a mixture of these. Various nutrients are added, sufficient for one season's growing, so frequently only planting and watering are required of the end-user. Planting is undertaken by first laying the bag flat on the floor or bench of the growing area, then cutting access holes in the uppermost surface, into which the plants are inserted.
Growbags were first produced in the 1970s for home use, but their use has since spread into market gardening and farming. They come in different sizes and formulations suited to specific crops.
Grow bags are usually made of felt or other non-woven, pressed fabrics, which have small holes in them to allow the free circulation of air. This free circulation of air benefits the roots by allowing them to more efficiently absorb water and nutrients from the soil.
Why Use a Plant Grow Bag?
Pots are heavy and difficult to move. Grow bags are lightweight. If you are growing on your balcony or anywhere weight is an issue or will need to move the containers during the growing season, fabric pots weigh practically nothing. It is only the weight of the soil that you have to deal with.
They are breathable and drain well. Unlike plastic, the fabric allows air to reach plant roots so the soil won’t get soggy. It is hard to overwater them.
They prevent plants from becoming rootbound. When a root reaches the side of the container it comes in contact with drier soil and more air. Instead of circling the pot and eventually strangling the plant, that root stops growing. Called “air pruning,” this encourages the plant to make new roots giving it a robust root system with many small root tips that can take in water and nutrients instead of a few long roots choking it. The plant can put more energy into top growth as well. Many growers swear that the plants in the grow bags do much better than those in plastic pots.
Soil is cooler in summer. Black plastic pots heat up in the summer sun. Since the bags can breathe, heat can escape. The felt-like fabric is more insulating than plastic so the soil stays a bit warmer when the weather cools down.