Mint grows rapidly and spreads very easily. It not properly contained, it can take over your garden.
The best method of containing it is to dig a hole larger enough for a 30cm container. Place the mint within the hole and refill with dirt. Within time, the mint will grow to the edges of the container.
Be very careful that it doesn’t propagate by layering. If you have one of the rarer types of mint, you can easily divide the roots and use the plants as gifts.
This hint is very simple but has effectively been used in many home herb gardens.
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