Nutrient Disorders in Vegetable Gardens

Most garden plant issues arise from insect and disease problems, nutrient deficiencies should only be treated when the disease and insect possibilities have first been explored. So long as the soil is relatively fertile and a proper soil pH is maintained Nutrient deficiencies are generally not a major problem.

Gardeners planting their favorite vegetables, herbs, fruits and berries in their home gardens is becoming increasingly popular. Supermarket varieties, not to mention low quality and high prices can not compare to the satisfaction of picking your own produce in your own yard, on your porch or patio. Even small indoor gardens and hydroponics are increasing in popularity.

Whatever type of gardening you engage in, it is vital that your plants are well nourished with the proper nutrients in the proper amounts at the proper times, and watered adequately to ensure a successful harvest.

Before you start adding possibly unnecessary and additional nutrients, you want to rule out other possible reasons for your plants symptoms.

You can actually do more harm than good with an incorrect diagnosis. Don’t over-fertilize, fertilizer burn can cause a burnt, wilted appearance.

Watch for insects attacking your plants. Look for holes gnawed through leaves, check the undersides of foliage for aphids or other small and sometimes barely noticeable varmints.

A cold snap can slow the growth and lead to temporary symptoms as described, a extended heat wave can do the same. Over or Under Watering can cause leaf yellowing, dryness, wilting.

Symptoms of Plant Nutrient Deficiency

Plants require both macro and micronutrients. Macronutrients are needed in larger quantities micronutrients in smaller quantities. All are needed to some degree.


We’ll be looking at some basic nutrient deficiencies in common garden plants, how to spot them, and treat them. Different plants will display varying signs, the following are the more common signs.

Calcium Deficiency

Calcium Deficiency in garden plants can lead can cause yellowing, pale and curling leaves and stunted growth, blossom-end rot on tomatoes, peppers and eggplants, blackened bean shoots, brown edges on cabbage leaves, irregular roots in carrots, beets and turnips, smaller potatoes and yams and other undesirable side effects. New leaves are frequently distorted, sometimes sickle shaped, and, in many cases, the plant will die off.

Sandy, acidic, and coarse soils generally contain less calcium. Overuse of fertilizers can also cause calcium deficiency. At times, even with sufficient calcium in the soil, the calcium present can be in an insoluble form which the plant can’t take in.

High phosphorus levels can create insoluble forms of calcium that the plants can’t take in. When calcium fertilizer is used it lowers the pH of the soil reducing the soil toxicity. If it is applied beyond the requirements it will stimulate the ammonium absorption by plants by as much as 100%.

Calcium is represented as “Ca” on fertilizer labels. Crushed/ pulverized eggshells are an excellent source of Calcium for gardens. [See: Eggshells as Fertilizer] Calcium deficiency can be rectified by adding agricultural lime to acidic soil, a pH of 6.5 is good, unless the plant in question requires a more acidic soil.

Potassium Deficiency

Potassium deficiency can cause a weak and / or deformed plant, and prematurely dropped blossoms. Fruits will sometimes drop before it is fully ripe. Older leaves sometimes have a wilted and burnt out bleached appearance around the edges and a yellowing between leaf veins, [chlorosis].

Adding potash – a potassium fertilizer is a good solution. It has a high potassium content that is released slowly, thus preventing an overdose. Inorganic fertilizers such as potassium nitrate, or potassium sulfate, are other options.

Seaweed meal, composted banana peels and wood ash also have high potassium content. Wood Ash as Fertilizer also helps with potassium problems. Adequate moisture is essential for effective potassium uptake.


Nitrogen in excess, will actually reduce production and hurt the quality of food that is produced. Nitrogen promotes the growth of foliage , green leaves, it’s great for lawns. Good for vegetables , but only in the proper quantities.

Excessive nitrogen leads to lush rich foliage but poor quality and low quantity fruit – vegetable production. By the same token vegetables grown for the foliage, such as lettuce may develop gigundous heads, but the taste is undesirable.

Nitrogen deficiency at times is an open invitation to insects, insects lead to more disease problems . Look for yellowing on older leaves near the plant base, other foliage is frequently a pale green , stems sometimes become flimsy and yellowish, creating a very noticeable wilting. noticeable. Plant development and crop maturing will slow drastically.

Phosphorous Deficiency

Phosphorous in fertilizer aids in root development and increases flowering ability as well as bloom size. Some high phosphorus fertilizers are marketed as ‘Bloom Booster.’ High-phosphorous fertilizer should be used when plants are being established in your garden.

Phosphorus deficiency is sometimes confused with nitrogen deficiency, it is uncommon, but does occur in areas with excessive rainfall or poor soil. Soil such as heavy clay or chalk soils. Cold weather can also cause a deficiency which is generally temporal. Especially susceptible are lettuce, spinach, carrots, and apples, some berries.

Symptoms include stunted growth, foliage that turns blue/green or Purple. The undersides of tomato leaves, as well as the veins and stems, sometimes turn purplish. Older growth leaves are affected initially, followed by new growth foliage. Fruits are small and acidic.

Phosphorous deficiency , if caught in time is easily controlled by applying organic phosphorous found in rock phosphate or a high-phosphorus fish fertilizer or bone meal.

Calcium, potassium, nitrogen and phosphorous are required macronutrients, nutrients that plants require in larger amounts. These nutrients sometimes need to be amended into the soil, even though they occur naturally in fertile soil at lower amounts.


Micronutrients that your plants require are iron, zinc, copper, boron and manganese.

Magnesium Deficiency

Magnesium deficiency occurs more frequently in light sandy soils that are strongly acidic, In light sandy soils magnesium can be easily leached away.

Organic mulch can help to prevent leaching and provide plants with sufficient amounts of magnesium as well as other nutrients. Excessive potassium, generally due to over fertilizing, can also contribute to magnesium deficiency.

Magnesium plays a vital role in photosynthesis, it forms the central atom of the chlorophyll molecule. A plant lacking adequate magnesium can not sufficiently engage in photosynthesis.

A plant will break down chlorophyll in its older foliage and transport the magnesium to new growth , which has a greater demand. Therefore, the first sign of magnesium deficiency is the chlorosis of old leaves – yellowing ,wilting.

After prolonged periods of magnesium deficiency, necrosis – Death and or degeneration of plant tissue occurs, which causes foliage and other parts to darken and wilt, which can occur rapidly at times. You will also notice premature dropping of older leaves.

In mild cases of Mg deficiency plants produce small, fibrous and woody fruits. Magnesium deficiency is sometimes mistaken with zinc or chlorine deficiencies, the symptoms are very similar. Adding Epsom Salts to the soil can rectify and prevent magnesium deficiencies.

Boron Deficiency

Boron effects fruit set and ultimate yields of fruits and vegetables. It influences how they process carbohydrates and distribute the natural sugars and pigments that control quality, taste, and color. A boron deficiency leaves plants stunted and deformed with misshapen buds and flowers.

New foliage is frequently curled and thicker than normal, in some plants there is an out of the ordinary yellow-orange tinge. Misshapen flowers hamper pollination and fruit set. when fruit does set it is usually very low quality.

In addition, roots fail to develop to their potential which inhibits the uptake of other nutrients. Severely deficient plants fail to produce any flowers, seeds, or fruit at all. See: Affects Of Boron On Vegetables and Fruits.

Related: Is Azomite Good for Plants?