While fruit and vegetables are prone to suffering the effects of nutrient deficiencies, it is relatively rare for hedge plants – especially when established – to be troubled to the same extent. If your hedge is showing similar symptoms to those detailed below, the chances are that it’s been recently planted in a soil with the wrong pH or it has too much or too little water, sun or shade.
Here, though, is a quick roundup of the most common problems associated with nutrient deficiency:
Nitrogen deficiency
• Nitrogen is highly soluble so can easily leach away.
Symptoms: Yellow foliage, possibly tinged with pink, and/or weak lanky growth
Action: Apply a high nitrogen fertiliser such as poultry manure or sulphate of ammonia. For a long term solution apply good quality organic mulch.
Potassium deficiency
• Potassium enables plants to control water uptake and to photosynthesise successfully. It is easily washed away on chalky and sandy soils while is held in clay
Symptoms: Leaves acquire a yellow or purple tiny and brown edges. Flowering / fruiting is compromised
Action: Apply a high potassium (K) fertiliser. Sulphate of potash or proprietary tomato feeds are ideal.
Phosphorus deficiency
Phosphorus deficiency is rare and generally restricted to clay soils in areas of heavy rainfall.
Symptoms: Foliage dulls and turns yellow. Growth slows
Action: Apply a high phosphate fertiliser such as bone meal
Magnesium deficiency
Hedging plants are not prone to magnesium deficiency – the two most common causes are the over-application of high potassium fertilisers and leeching on sandy soils.
Symptoms: Foliage turns yellow between the veins occasionally accompanied by red/brown tinting and early leaf drop
Action: Spray Epsom salts fortnightly in summer.
Other Deficiencies
Hedging plants rarely – if ever – succumb to deficiencies of three important trace elements: Molybdenum, Boron and Manganese.
The picture shows a distressed looking Box – but it ISN’T blight. The plant is actually suffering from potash deficiency. A top dressing of fresh compost (John Innes No 3 for example) and a dose or two of fertilizer (one formulated for tomatoes will be ideal) and the plant will soon return to its green glory.