How to recognise it
Nutrient deficiencies can cause a wide range of symptoms, though most will cause an overall reduction in growth. The most common specific symptoms and likely nutrient deficiencies are listed below.
What causes it
Plants require a wide range of nutrients to survive. Some of these, such as nitrogen, potassium and phosphorous, are required in high quantities. However, the more minor nutrients, such as manganese and zinc, are just as vital even though smaller quantities of them are required.
Why it’s a problem
Nutrient deficiencies can reduce plant growth, cause vulnerability to pests and diseases, and ultimately may kill the plant.
Where you are likely to find it
Depending on the nutrient which is deficient, the symptoms are likely to present in different ways on different parts of the plant. Below is an overview of possible symptoms and the deficiency/ies which can cause them.
| Symptom | Likely nutrient deficiency |
|---|---|
| General yellowing (chlorosis) of leaves, especially older leaves. Leaves are reduced in size. | Nitrogen |
| Purple or red discolouration of leaves (particularly common on brassicas), occurring on older leaves first. | Nitrogen |
| Flowering and fruiting may be reduced and delayed. In particular, potatoes may produce few tubers, apples are smaller and redder, and leafy vegetables are stunted. | Nitrogen |
| Mottling or yellowing (chlorosis) of leaves with dead areas at tips and margins, mostly older leaves affected. Leaf edges may curl downwards. Brown spots may appear on the underside of the leaves. | Potassium |
| Stems grow weak or narrow and may die back. | Potassium |
| Tomato fruits grow with some areas unripened, giving a blotchy effect. | Potassium |
| Plants become darker green or blue-green with red or purple tints. | Phosphorous |
| Stems become stunted. | Phosphorous |
| Leaves are smaller and older leaves become dark brown and die prematurely. Potato leaves may have scorching at the margin. Currant leaves can turn a dull bronze colour with brown/purple spots. | Phosphorous |
| Flowering and fruiting may be reduced and delayed. | Phosphorous |
| Die back of shoot and root tips. | Calcium |
| Younger leaves die back at the tips and margins (especially on lettuces). | Calcium |
| Black/brown leathery patches occur at base of tomato and pepper fruits (“blossom end rot“). | Calcium |
| Dark spots or pits appear on the surface of apple fruits with brown spots within the flesh (“bitter pit”). The flesh may also become translucent and the fruits may not store well at low temperatures. | Calcium |
| Browning of the leaves (of the crown or within the vegetables) of Brussels sprouts. | Calcium |
| Long spots on the roots cause them to crack open. | Calcium |
| Centres of celery or chicory crowns become blackened and stunted. | Calcium |
| Shoots of potatoes become elongated with rolled leaves and producing many very small tubers. | Calcium |
| Mottling or yellowing (chlorosis) of leaves, particularly of the inter-veinal areas, which may also become red/purple (particularly on red-pigmented plants such as beetroot) and develop dead spots. Leaf tips and margins turn upwards. The older leaves will be the first affected. | Magnesium |
| Apple trees may lose their leaves prematurely. | Magnesium |
| Veins and inter-veinal areas become light green on younger leaves. | Sulphur |
| Leaves wilt and yellow (chlorosis) with dead spots, they may become bronze in colour. | Chlorine |
| Roots are stunted in length and the root tips become thickened. | Chlorine |
| Yellowing (chlorosis) of inter-veinal areas of younger leaves, so the veins stand out as dark green. | Iron |
| Plants’ yields reduce and they may eventually fail to flower or fruit altogether. | Iron |
| Stems grow shorter and narrower. | Iron |
| Roots fail to grow longer. | Boron |
| Younger leaves become light green at their base, die back from their tips and may become twisted (including lettuce leaves). | Boron |
| Stems become distorted and die back at their tips. | Boron |
| Blackened flesh (in patches or rings) within the hearts of beetroot, swedes and turnips (“heart rot”). Corky patches may appear on shoots, leaf stalks and other areas. | Boron |
| Discoloured, browning heads on cauliflowers and Brussels sprouts (“brown curd”). They may taste bitter. | Boron |
| The leaves of apple and pear trees may become narrower and thicker, cracking easily and with corky patches developing. Corky areas may also develop on and inside the fruit (“corky pit”). | Boron |
| Celery leaves yellow and the leaf stalks become brown, corky, mottled and cracked. | Boron |
| Sweetcorn cobs don’t develop, with die back of the growing point and white stripes appearing on the leaves. | Boron |
| Yellowing (chlorosis) or browning of inter-veinal areas of young and old leaves followed by dead spots appearing. | Manganese |
| Browning of the centre of peas and beans (“marsh spot”). | Manganese |
| Rolled leaves with yellow patches on beetroot (“speckled yellows”). | Manganese |
| On some plants, such as potatoes, younger leaves may become pale and roll upwards. | Manganese |
| Leaves and internodal areas reduce in size. | Zinc |
| Leaves have distorted margins and yellowing (chlorosis) of the inter-veinal areas, mainly on older leaves. | Zinc |
| Younger leaves become dark green or blue-green, twisted, distorted and often have dead spots. | Copper |
| Dead spots appear at leaf tips. | Nickel |
| Yellowing (chlorosis) of leaves’ inter-veinal areas, appearing on older leaves first before moving to younger leaves. Dead areas form, starting in the inter-veinal areas. | Molybdenum |
| Leaves become thin and strap-like on cauliflowers (“whiptail”). | Molybdenum |
How to prevent it
Ensure that you understand the nutrient requirements before purchasing and planting plants. This is particularly important with ericaceous plants, which will quickly become nutrient deficient in alkaline soils.
If you grow plants in containers ensure that you refresh the compost each year and provide them with a regular dose of fertilisers.
How to get rid of it
Most deficiencies can be managed quickly and effectively with the application of an appropriate fertiliser (which contains a high proportion of the missing nutrient). However, if you have a plant which is in the wrong soil type (either in terms of pH or overall nutrient levels) then the simplest solution is to move the plant, otherwise you’ll be constantly fighting an uphill battle to keep it healthy.
Is it good for anything?!
No.
Other useful information
We have further information on some specific nutrient deficiencies:
