Garden soil is heavy, the water can’t drain from it freely. Clay particles in soil fit tightly together and prevent water from draining away and air from entering, which is not good for plant roots.
If you want to use the garden soil, you’ll need to amend it. Mix it with compost or well-rotted manure, peat, coir, etc. so that it will become light.
Most of the container gardeners do this—filling the pot to the top. While it doesn’t do any harm to your plant, it makes watering a difficult job. The best idea is to leave an inch of space between the rim of the pot and the top layer of the soil.
The soil in a container for months and years gets compacted, this thwarts the drainage and aeration. That’s why it is important to change your potting soil, once a year, for the optimum growth of plants.
Soil changing procedure is most important if your plant is suffering from soil-borne diseases. You may think it’s a costly idea as potting mixes are not cheap, and you can’t buy them again and again.
To avoid this, make your own potting mix. We’ve shared the link above already, and you can also find dozens of recipes on the web.
Pro Tip: If you don’t want to change soil, scrap and replace 1/3 of the top layer with organic matter like compost or manure.
Plants are not the same and can’t be grown in the same type of soil. Each plant requires a different soil type. Succulents need well-draining soil that doesn’t retain moisture, whereas some plants prefer soil to be consistently moist like the calla lily.
Also, consider your potting soil type based on where you will be keeping them and your climate. For example, a plant kept outdoor in a hot tropical climate is going to need soil that retains some moisture and remains cool compared to a plant
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