Copper Deficiency in Hydroponically Grown Plants
Copper deficiencies rarely occur in hydroponically-grown plants, especially when using a reputable hydroponic nutrient range. When a copper deficiency does occur it is usually mistaken for- and then treated- as an iron deficiency, leading to a range of other problems.
The key to preventing copper deficiencies is to ensure that adequate levels are being regularly supplied through nutrition; as well as maintaining pH balance.
WHY IS COPPER IMPORTANT TO PLANT HEALTH?
Copper plays a critical role in:
- Oxidation-reduction reactions in conjunction with zinc
- Chlorophyll production
- Formation of lignin in cell walls (lignification)
- Protein synthesis
- Seed production & fertility
- Natural defences against diseases such as powdery mildew
MAIN CAUSES OF COPPER DEFICIENCY
Like many other micronutrients, copper deficiency can be caused by:
- Malnutrition (low EC)
- High pH levels
- Low-quality nutrients with insufficient amounts of copper
- Excess potassium, phosphorus & zinc can cause copper to be antagonised and locked out.
- Low root zone temperatures
KEY SYMPTOMS OF COPPER DEFICIENCY IN PLANTS
- Root growth is stunted impacting nutrient uptake
- The entire plant wilts, similar to the look of over fertilisation
- Main stem can become brittle
- Some plant varieties will become overly soft/bendy to touch
- New growth stops or forms slowly, is pale in colour and will quickly stop growing
- Delayed flowering
HOW TO FIX A COPPER DEFICIENCY?
Correct & maintain pH levels
Adjust nutrient solution by using a quality pH down product. The pH range that is for best for absorption of copper is 5.0-6.0. Copper is most available at 5.0. Test daily.
Add a fulvic acid product
Add 0.5ml of Mills Start-R per 1L water to your normal feeding program, up to early stages of flowering.
Copper is an immobile element, which means the plant cannot translocate copper from older growth to new growth. A foliar spray of Mills Vitalize can also correct this problem. Mix 0.1ml of Vitalize to 1L of water, adjust to pH 5.0-6.0 Mist the entire plant just after lights turn off to avoid any light scorching.
Low root-zone temperature
Give your plant’s metabolism a boost by keeping root-zone temps between 18-21°C. Use low wattage gadgets like heat bars and heat mats to help.
A-Grade Tip: Copper deficiency make vegetable crops susceptible to fungal diseases like septoria. A weekly spray of products like Rid-a-Rot or PureCrop1 will help keep fungal infections like septoria and powdery mildew at bay.
Shown above: Early copper deficiencies can be mistaken as nutrient excess
Shown above: The new growth is very small & contorted. Note the pinkish hues forming at the rear of the leaf. The stems on this plant were very soft and bendy to touch