What is the effect of HCO3?

HCO₃ is bicarbonate. This substance increases the pH value of the substrate. In this article, we discuss the effect of bicarbonate, when it is desirable, when it is not and where the substance comes from.  

Neutralising pH value

If the pH value is too low, an increase in bicarbonate can be beneficial to your plants. As it happens, if the pH value is too low, the plant may absorb insufficient sulphur or nitrogen, which can cause poisoning. Bicarbonate can then neutralise the pH value. But if the pH value is already on the high side, too much HCO₃ is undesirable. Your plants will be less able or unable to absorb a number of nutritional elements and the water turns green due to algae. Plants can even die. 

Not a nutritional element

Bicarbonate is not a nutritional element and is not added to potting soil formulas. However, the substance may be present in these and will be listed in the potting soil’s nutritional analysis. Bicarbonate occurs due to liming. It is often also found in clay, compost and water. In addition, bicarbonate can originate from CO₂ in the root environment if the pH value increases. Bicarbonate can occur during growth due to pH-increasing fertilisation. 

If you want to prevent the occurrence of bicarbonate from a pH-increasing fertiliser, we advise you to adapt the fertiliser to make the formulation more acidic in composition.

How can you tell if the pH value is too high?

If the pH value is too high, you will first notice it at the top of the plant. The leaves will change from light green to deep yellow and the tips may curl upwards. The leaf stalks often take on a purple hue.

Need personal advice?

Do you need personal advice about the HCO₃ level in your potting soil? We would be delighted to assist. We have various products that can improve the health of your plants. If bicarbonate causes an excessively high pH value, you can combat this with BAC pH- phosphorous. It is highly soluble in water.