Nitrogen is an essential element for the healthy growth of plants. Plants lacking nitrogen will show general yellowing of older leaves at the bottom of the plant.
Identify the problem
General yellowing of lower (older) leaves of plants is often caused by lack of nitrogen. But the older leaves of many plants, yellow and fall naturally. Nitrogen deficiency will also cause upper (newer) leaves to become a paler green. So check for yellowing lower leaves and pale green upper leaves.
Most plants absorb nitrogen through their roots as nitrate or ammonium. These forms are readily dissolved in water and so are prone to be washed away by rain and watering. Fertilisers and manures should be of the types that help bind nitrogen in the soil so that it is available to the plant roots.
Nitrogen deficiency is not always caused by insufficient nitrogen in the soil. On occasions there might be something that is preventing the plant absorbing available nitrogen. this can be over-watering causing roots to lack oxygen and consequently being unable to absorb nutrients.
Nitrogen is involved in many aspects of the growth of plants. It helps promote rapid growth, increased seed and fruit production and strong green growth of leaves and photosynthetic parts of the plant.
- Check for yellowing lower (older) leaves and lighter green of upper (younger) leaves. Also check that the roots are not sitting in saturated soil preventing nitrogen uptake.
- If the symptoms suggest nitrogen deficiency apply an appropriate organic fertiliser. Kiwicare's LawnPro 7-Day-Green. Each has an ideal balance of nitrogen, phosphorous and potassium (N:P:K) plus trace nutrients and humics for each plant type.
- When planting bedding plants, vegetables, trees and shrubs add Gro-Sure Planting Magic to the hole and soil fill. This gives the plants the best root establishment and to provide all the nutrients, organic matter and humus the plant will need for the whole season.