Sustainable houseplants: potting soil

My plants engage me during times that I want to stay at home. These days are pretty common, so I am really grateful to have discovered this passion recently. Having houseplants is an art. So how do you really ensure sustainable houseplants?
Having houseplants seems okay for the environment, right? Unfortunantely the opposite is true. When you buy from a regular grower, a ton of chemicals have been used to get the plant to grow flawlessly. Mostly plants are sold in plastic pots, potting soil is sold in plastic packaging, nutrients are chemical and so are pest repellants. Luckily nowadays many alternatives have been developed to tackle these ‘problems’.


The potting soil problem


Besides the packaging there’s another problem. The main component is almost always peat. This pre-fossil fuel is mined in nature reserves. Peat consists of plant residues more than a thousand years old, and also carbon. Therefore it’s seen as a non-renewable fuel, because its components are created so slowly.
Peat is not a nutrient for the plant. Its main function is to provide the airiness and the structure in the potting soils we know. The retention of moisture can be solved by adding a bit of sphagnum (also called peat moss). There is a lot of research going on to ecologically grow sphagnum. You can’t replace peat with just one component. You need multiple. As a consequence the potting soil will seem coarser, but our houseplants don’t care.
Buying bio potting soil doesn’t ensure that no peat has been used. Peat is natural as it originates from the ground, hence it can bear the label bio. Thus bio doesn’t mean sustainable houseplants per se.

make your own potting soil


The first step towards sustainable houseplants: creating your own potting soil
The best way to be sure what components your potting soil is made of is to create your own! This base recipe is easy to create. You need garden soil (sand or loam), compost and coarse sand or rhine sand. Use 4 parts of garden soil, 4 parts of compost and 2 parts of coarse sand or rhine sand and mix them. Now you have perfectly usable potting soil. This is not easy to do if you live in an apartment, like I do. Definitely try this if you have a garden!
Coconut fiber is also used a lot to increase the airiness of the soil. Do you want to be even more ecological? Then try leaf compost of oak, beech or birch. These leafs can best be gathered during winter. Let them compost for 2 years.
 

Potting soil without plastic


Potting soil, with or without peat, and other non-durable materials are packaged in plastic bags. There are no durable alternatives to this day. You can reuse the plastic bags for other things after you used the soil, but this isn’t the answer that I would like to give. When you create your own soil you can use these old bags to store it in, or use the bags to create your compost.
These days there are some places where you can repot your plants on the spot so you don’t have to buy any plastic packaging. This soil is bought in bulk so the plastic waste is reduced by a lot. In these places you can sometimes also buy soil and transport it in your own packaging.