The three Minerals soil needs to grow healthy plants

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Signs of a deficiency of essential minerals in soil

What to do if soil is deficiant in Magnesium, Potassium or Calcium

The positive effect of Magnesium, Potassium and Calcium on gardening and the negative effect of a deficiency are explained in the article. 
  • Essential Minerals for healthy soil are  Magnesium, Potassium and Calciu
  • Signs for the gardener to look out for deficiency and remedial actions to take.....

A shortage of Magnesium is often caused by watering too much. It is worth noting that Calcium cannot be used by garden plants without Magnesium. And heavy rain and excessive watering will wash the Magnesium into the lower layers of the soil, out of reach of most garden plant roots.

It's brought back up by deep rooting plants like trees. That's why it's a very good idea to spread falling leaves back onto the soil, instead of sending them off in your green bag.

Magnesium deficiency is recognized by pale green leaves and blossom and fruit rot. Regular sprinkling of dolomite or Epsom salts onto the soil helps, but the best and most natural way of getting Magnesium back into the soil is spreading tree leaves over the garden.


Potassium is important for a plant's ability to withstand extreme cold, hot temperatures, drought and pests

For soil severely deficient in potassium add rock potash. Rock potash contains 10.5 percent worth of potassium and is released slowly so you won't overdose your plants. Wood ash applied directly to the soil also adds potassium. 

Symptoms of potassium deficiency include yellowing of the lower leaves and in severe cases leaf-tip die-back



Calcium is essential in your garden soil. Plants need calcium for the growth of its young roots and shoots. Without calcium, plants can't grow. 

However, calcium deficiency in the soil is very rare. Not watering evenly (to dry and then to wet) is the main cause of calcium deficiency.  A soil test is the best way to find out. Adding horticulture lime will help, but I wouldn't spend to much time worrying about a lack of calcium unless your soil is extremely sandy.