You can simply take it easy: depending on your preferences, you can "go wild" here. However, a sustainable approach to the "how" is also helpful here. In any case, there is no more sustainable or healthier food than freshly harvested and used foods.
Tip: Use high-quality seeds or special seed pads such as foodigence, as otherwise various chemicals (e.g. pesticides) are used in the cultivation or the seeds come from unclear sources.
Tip: Choose your soil carefully, as there is a virtually endless range of varieties available. Ideally, peat should not be included, and soil can be reused over and over again if it is enriched with compost or organic fertilizer. Instead of throwing away unused flowerpots, the soil can be collected and reused.
