Blueberry Nutrient Deficiencies | Berry Diagnostic Tool

Nitrogen deficiency (N deficiency)

Nitrogen deficiencies are common in blueberries. Note the light green color (chlorosis) is uniform across the leaves with no particular pattern or mottling. Other symptoms of nitrogen deficiency include reduced shoot growth, numbers of new canes and yield. Nitrogen deficient leaves may develop early fall color and then drop off.

Two blueberry plants. Plant on left has yellow-green leaves throughout, plant on right has dark blue-green leaves. — Nitrogen deficiency on ‘Bluecrop’ blueberry. Plant on the left did not receive adequate nitrogen fertilizer.

Iron deficiency (Fe deficiency)

Interveinal yellowing is caused by iron deficiency, but is symptomatic of high soil pH. A high soil pH (>5.2) results in the inability of the blueberry plant to use iron, causing a lack of chlorophyll production.

Blueberry leaves with dark green veins and pale yellow leaf tissue.

Iron deficiency symptoms develop first in young leaves. Lowering the pH with sulfur will usually correct the problem.

Small blueberry plant with yellow leaves with green veins. Some of the yellow leaves have bronze color along outer margins.

Potassium deficiency (K deficiency)

Potassium deficiency results in marginal leaf burn. It is not common, but has been observed in very sandy soils.

Blueberry leaves with dry, brown tissue along leaf edges. The border between healthy green tissue and browned tissue is sharp, but pattern of browning is irregular along leaf margin and may extend far into the leaf towards the central vein. — Potassium deficiency in blueberry with characteristic marginal leaf burn.

Phosphorus deficiency (P deficiency)

causes purple coloration in blueberry leaves, but this is rarely observed in the field. Blueberries have a low P requirement. If the pH is too high (>5.2) for adequate P uptake, other nutrients likely will be unavailable as well.

Blueberry plant in pot of sand. Plant is short and has deep purple tinged leaves. Text on image says "minus P"

Magnesium deficiency (Mg deficiency)

Mangnesium deficiency is common in acid soils. Lack of Magnesium causes interveinal reddening because chlorophyll production is reduced. Symptoms begin as an interveinal yellowing and progress to a bright red. Leaves at the bases of young shoots are most likely to exhibit symptoms first. Young leaves at the tips of shoots are seldom affected.

Blueberry leaf with maroon coloration and green veins. Red color is deepest at tip of leaf.

Boron deficiency (B deficiency)

In rare cases, boron deficiency causes die back of canes without wilting or cankers present. A leaf analysis can verify this diagnosis.

Blueberry twigs with fruit and leaves. Fruit is shriveled and brown, twigs and leaves appear dead.

More information:

Blueberry nutrition – Michigan State University Extension

Suspected nutrient deficiencies can be verified with a soil and/or foliar analysis done through Agro-One.

Use these resources if you need additional help with diagnosis and to find solutions to your problem.