If your plants look discolored, stunted, or have low yields, a nutrient deficiency might be the culprit. Many nutrients other than nitrogen, including calcium and phosphorus, play a vital role in plant growth. If your plant exhibits a deficiency symptom, make sure to get a soil test before you add any amendments.
| Nutrient |
Function |
Deficiency symptoms |
Source |
| Nitrogen |
Required for all phases of growth and development |
Lower leaves light green or yellowish; plant is stunted. |
Blood meal, composted poultry manure, feather meal. |
| Phosphorus |
Strengthens stems, helps in resistance to pests and diseases, fruiting and flowering |
Lower leaves and stem are reddish; upper leaves are dull, pale; failure to flower or produce fruit. |
Bone meal, colloidal or rock phosphate, fish meal |
| Potassium |
Required for formation of all sugars, starches and proteins; contributes to cold-hardiness; root development. |
Lower leaves spotted, mottled or curled; underdeveloped roots, stem tissue may appear weak |
Composted manure, wood ashes, greensand, seaweed. |
| Calcium |
Required for cell growth and division, helps plants use nitrogen |
Tipburn on lettuce, blossom-end rot in pepper and tomatoes. |
Bone meal, gypsum, lime. |
| Sulfur |
Constituent of protein and certain vitamin complexes. |
New leaves are yellowish. |
Composted manure, gypsum, Sul-Po-Mag. |
| Magnesium |
Constituent of chlorophyll; required for enzyme action. |
Whitish patches appear first on older leaves, between leaf veins. |
Sul-Po-Mag, Epsom salts |
