
Calcium (Ca) deficiency is a plant disorder that can be caused by insufficient level of biologically available
calcium
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...
in the growing medium, but is more frequently a product of low
transpiration
Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers. It is a passive process that requires no energy expense by the plant. Transpiration also cools plants, c ...
of the whole plant or more commonly the affected tissue. Plants are susceptible to such localized calcium deficiencies in low or non-transpiring tissues because calcium is not transported in the
phloem
Phloem (, ) is the living tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as ''photosynthates'', in particular the sugar sucrose, to the rest of the plant. This transport process is ...
. This may be due to water shortages, which slow the transportation of
calcium
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...
to the plant, poor uptake of calcium through the stem,
or too much
nitrogen
Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...
in the soil.
Causes
Acidic, sandy, or coarse
soil
Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...
s often contain less calcium. Uneven soil moisture and overuse of
fertilizer
A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Man ...
s can also cause calcium deficiency. At times, even with sufficient calcium in the soil, it can be in an insoluble form and is then unusable by the plant or it could be attributed to a "transport protein".
Soils containing high phosphorus are particularly susceptible to creating insoluble forms of calcium.
Calcium and
magnesium
Magnesium is a chemical element; it has Symbol (chemistry), symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 ...
are opposed within the plant cells, and have antagonistic interactions. As a result, a homeostatic balance between Ca and Mg within the plant is necessary for optimal growth and proper development.
Symptoms

Calcium deficiency symptoms appear initially as localized tissue
necrosis
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who i ...
leading to stunted plant growth,
necrotic
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who is ...
leaf margins on young leaves or curling of the leaves, and eventual death of
terminal buds and
root tips. Generally, the new growth and rapidly growing tissues of the plant are affected first. The mature leaves are rarely if ever affected because calcium accumulates to high concentrations in older leaves. Calcium deficiencies in plants are associated with reduced height, fewer nodes, and less leaf area.
Crop-specific symptoms include:
;
Apple
An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are agriculture, cultivated worldwide. The tree originated ...
: '
Bitter pit' – fruit skins develop pits, brown spots appear on skin and/or in flesh and taste of those areas is bitter. This usually occurs when fruit is in storage, and
Bramley apples are particularly susceptible. Related to
boron deficiency, "water cored" apples seldom display bitter pit effects.
;
Cabbage
Cabbage, comprising several cultivars of '' Brassica oleracea'', is a leafy green, red (purple), or white (pale green) biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage ( ''B.& ...
,
lettuce
Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae mostly grown as a leaf vegetable. The leaves are most often used raw in Green salad, green salads, although lettuce is also seen in other kinds of food, such as sandwiche ...
and
brussels sprout
The Brussels sprout is a member of the Gemmifera cultivar group of cabbages (''Brassica oleracea''), grown for its edible buds.
Etymology
Though native to the Mediterranean region with other cabbage species, Brussels sprouts first appeared i ...
s :There is some evidence that plants like lettuce are more likely to experience tipburn (burned edges of leaves) if they're experiencing a deficiency of calcium.
;
Carrot
The carrot ('' Daucus carota'' subsp. ''sativus'') is a root vegetable, typically orange in colour, though heirloom variants including purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the wild ...
: '
Cavity spot' – oval spots develop into craters which may be invaded by other
disease-causing organisms.
;
Celery
Celery (''Apium graveolens'' Dulce Group or ''Apium graveolens'' var. ''dulce'') is a cultivated plant belonging to the species ''Apium graveolens'' in the family Apiaceae that has been used as a vegetable since ancient times.
The original wild ...
: Stunted growth, central leaves stunted.
;
Tomato
The tomato (, ), ''Solanum lycopersicum'', is a plant whose fruit is an edible Berry (botany), berry that is eaten as a vegetable. The tomato is a member of the nightshade family that includes tobacco, potato, and chili peppers. It originate ...
es and
peppers:'Blossom end rot' – Symptoms start as sunken, dry decaying areas at the blossom end of the fruit, furthest away from the stem, not all fruit on a truss is necessarily affected. Sometimes rapid growth from high-nitrogen fertilizers may exacerbate blossom end rot. Water management and preventing water stress is key to minimizing its occurrence.
Although it was once common knowledge that blossom end rot was caused by calcium deficiencies, there are also other proposed causes.
Treatment

Calcium deficiency can sometimes be rectified by adding
agricultural lime
Agricultural lime, also called aglime, agricultural limestone, garden lime or liming, is a soil additive made from pulverized limestone or chalk. The primary active component is calcium carbonate. Additional chemicals vary depending on the mineral ...
to acid soils, aiming at a
pH of 6.5,
unless the subject plants specifically prefer acidic soil. Organic matter should be added to the soil to improve its moisture-retaining capacity.
However, because of the nature of the disorder (i.e. poor transport of calcium to low transpiring tissues), the problem cannot generally be cured by the addition of calcium to the roots.
In some species, the problem can be reduced by prophylactic spraying with
calcium chloride
Calcium chloride is an inorganic compound, a Salt (chemistry), salt with the chemical formula . It is a white crystalline solid at room temperature, and it is highly soluble in water. It can be created by neutralising hydrochloric acid with cal ...
of tissues at risk.
Plant damage is difficult to reverse, so corrective action should be taken immediately, supplemental applications of
calcium nitrate
Calcium nitrate are inorganic compounds with the formula Ca(NO3)2(H2O)x. The anhydrous compound, which is rarely encountered, absorbs moisture from the air to give the tetrahydrate. Both anhydrous and hydrated forms are colourless salts. Hydrated ...
at 200 ppm nitrogen, for example. Soil
pH should be tested, and corrected if needed, because calcium deficiency is often associated with low pH.
Early fruit will generally have the worst symptoms, with them typically lessening as the season progresses. Preventative measures, such as irrigating prior to especially high temperatures and stable irrigation will minimize the occurrence.
See also
*
Blackheart (plant disease)
*
Plant nutrition
Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element i ...
*
Horticulture
Horticulture (from ) is the art and science of growing fruits, vegetables, flowers, trees, shrubs and ornamental plants. Horticulture is commonly associated with the more professional and technical aspects of plant cultivation on a smaller and mo ...
References
*Hopkins, William G., Norman P.A. Hüner. ''Introduction to Plant Physiology''. London:
Wiley & Sons, 2009.
*Nguyen, Ivy. “Increasing Vitamin D2 with Ergosterol for Calcium Absorption in Sugarcane.”
UC Davis
The University of California, Davis (UC Davis, UCD, or Davis) is a Public university, public Land-grant university, land-grant research university in Davis, California, United States. It is the northernmost of the ten campuses of the University ...
COSMOS. July 2009. 17 October 2010
NGUYEN_IVY.pdf*Simon, E.W. “The Symptoms of Calcium Deficiency in Plants.” ''
New Phytologist
''New Phytologist'' is a peer-reviewed scientific journal published on behalf of the New Phytologist Foundation by Wiley-Blackwell. It covers all aspects of botany and was established in 1902 by Arthur Tansley, who served as editor until 1931.
M ...
'' 80 (1978):1-15.
Notes
External links
Blossom end Rot videoExample of blossom end rot on Roma tomatoes- The Ohio State University Extension
{{PlantMineralDeficiency
Physiological plant disorders
Biology and pharmacology of chemical elements
Deficiency (Plant)
Tomato diseases