Planting your own herbs and spices
For edibles like herbs you should choose an organic soil to avoid chemicals. How many containers you need depends on the herbs you are planting, some herbs are more thirsty than others and you will need to separate them. Plant the seeds near the surface of the soil. Harvest your herbs regularly to keep them fresh.
Choosing a soil
Healthy soil is loose enough to let the roots spread easily, but also compact enough to keep its moisture. Let pieces of bark, stones and other misfits stay in the soil: rough soil is a good thing. Bigger plants need more nutrition from their soil. Fertilizing your plants during spring and summer will make up for the extra nutrition they need, resulting in healthier plants.
Replanting flower pots
Every year or so plants should be replanted in a bigger flower pot, adding more soil. The new flower pot should about double the size of the previous pot, no more, or the soil will keep its moisture for too long which is bad for the roots. Adding clay pebbles (LECA) to the bottom of the pot is a good way to allow excess water to drain from the soil. Around 2cm thick layer.
Miscoloring of the leaves, slow growth or sensitivity to cold weather are early signs of lack of nutrition in the soil. Plants contained in a pot or other container need constant fertilizing to grow properly. When dealing with smaller pots it's easiest to add fertilizer to the water when watering, or stick fertilizing sticks into the soil. Spring is the best time to fertilize your plants. After July in the Autumn, you shouldn't use fertilizer with high amounts of nitrogen. The best results are gotten from choosing a good soil: fertilizing comes after.