Nutrient deficiencies of perennials: Part 9 of 12

Pachystachys lutea (yellow shrimp plant)

Pachystachys lutea (yellow shrimp plant), sometimes called lollipop plant, is a versatile tropical perennial hardy in USDA Hardiness Zones 9-11. It can be a containerized ornamental or as a landscape item in mass, borders, hedges or as a specimen plant. Yellow shrimp plant performs best in moist, acidic to slightly alkaline soils, full- to part-sun conditions and is susceptible to insects including aphids, mealybugs, mites and whiteflies.

Fertilization needs

Fertilizer recommendations are limited; however, studies have shown it to perform best in substrates low in organic matter. It produces more flowers with increased postharvest longevity when more nitrate nitrogen than ammoniacal nitrogen is applied. Overall, nitrogen at 175-200 parts per million from a complete fertilizer on a continual liquid fertilizer program will maintain dark foliage with desired flower production.

Nutrient deficiencies can occur during production, especially during winter when greenhouse night temperatures are below 60°. Common symptoms are intervenal chlorosis of the young leaves and lower leaf yellowing.

Fertility monitoring and management for yellow shrimp plant requires a balancing of the plant’s needs. Growers must be aware and manage the root substrate pH and electrical conductivity and provide adequate, but not excessive, levels of all essential elements. Using a plant diagnostic laboratory to identify the source of problems is still the best way to ensure accurate diagnoses, since many nutritional, physiological, insect and disease problems can mimic each other.

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Nutrient deficiency descriptions are unavailable for most perennials, yet growers must often make quick diagnosis. A research project initiated at the University of Florida in Milton documented deficiency symptoms in vegetatively propagated yellow shrimp plant to assist growers.

Pictures related to the nutrient deficiencies series may accessed by viewing the PDF files of the pages that originally appeared in GMPRO magazine: Page 1. Page 2. Page 3. Page 4. Page 5. Page 6. Page 7. Page 8.

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Nitrogen (N)

Despite its mobile nature, nitrogen deficiency (pale green to yellow tissue) is first expressed in the young and youngest leaves.

Nitrogen-deficient plants have narrower leaf blades than the control.

At the advanced deficiency stage, veins become whitish-green and the interveinal areas and leaf tips of older leaves express reddish-brown to dull black necrotic spots.

Phosphorus (P)

Oldest to youngest leaves are darker green when compared to the control’s leaves.

As symptoms progress, the recently mature leaves cup downward and develop chlorosis on the margins and interveinal regions.

Under advanced deficiency symptoms, mature leaves become dull green and slightly twisted.

Potassium (K)

Potassium-deficient plants first express a faint chlorosis on young leaf tips.

Potassium-deficient plants have darker green leaf bases with greenish-yellow tips and shorter internodes when compared to the control.

Eventually the older leaf margins buckle and express a reddish-brown necrosis. Young leaf tips also express a reddish-brown necrosis.

Calcium (Ca)

One of the initial symptoms of calcium deficiency is curled and distorted leaves.

Calcium-deficient plants have spindly stems, curled under mature leaves and chlorotic shoot tips.

As deficiency symptoms become more advanced, the young shoot tips turn pale yellow and curve under.

Magnesium (Mg)

Magnesium deficiency begins as a faint interveinal chlorosis on the recently mature leaves.

As deficiency symptoms progress, a greenish-yellow interveinal chlorosis appears over the entire leaf blade. Leaf margins roll inward. 

Advanced symptoms of magnesium deficiency include completely rolled mature leaves and dull green young and youngest leaves.

Sulfur (S)

Initially, sulfur-deficient plants show signs of interveinal chlorosis on the recently mature leaves.

As symptoms progress, shoot tips become severely chlorotic, recently mature leaves droop downward and flower buds fade to dull, whitish-yellow.

Recently mature leaves develop irregular-shaped, brownish-red to tan patches on their bases.

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Boron (B)

Boron-deficient plants initially express compressed shoot tips and shorter internodes than the control.

The youngest leaves turn upright, and the young leaves turn brittle. Flowers cease to develop.

At the advanced stage, deformed young leaves have wavy margins, chlorotic bases and necrotic midsections.

Copper (Cu)

Copper-deficient plants have shorter internodes when compared to the control and have dull, blue-green foliage.

As deficiency symptoms progress, recently mature and young leaves develop a distinct interveinal chlorosis.

Small, brown spots soon develop within splotchy, yellow chlorotic spots on recently mature leaves.

Iron (Fe)

Iron-deficient plants first express lighter green recently mature leaves.

Secondary deficiency symptoms include pale green to light yellow youngest, young and recently mature leaves.

Advanced symptoms include a yellowish-white interveinal chlorosis over the entire surface of recently mature, young and youngest leaves.

Manganese (Mn)

Manganese deficiency is expressed on the recently mature and young leaves as a faint interveinal chlorosis.

Manganese-deficient plants are less rigid than control plants. The chlorosis becomes more defined on the upper growth while the older leaves develop a faint interveinal chlorosis.

As symptoms progress, the recently mature leaves express a brownish-red necrosis between their deep green veins.

Zinc (Zn)

Shoot growth on zinc-deficient plants is lighter green than the control.

Deficiency symptoms develop rapidly on the plant. Recently mature leaves are thick and brittle with severe interveinal chlorosis.

Under advanced deficiency conditions plants are less dense, axillary shoots are thin and narrow, and young leaves are straplike.

- James L. Gibson, Kathryn Campbell, Sharon Wombles and Jude Groninger

James Gibson is assistant professor, Jude Groninger is senior laboratory technician, Sharon Wombles and Kathryn Campbell are former undergraduate research assistants, University of Florida, Institute of Food and Agricultural Sciences, West Florida Research and Education Center, 5988 Highway 90, Building 4900, Milton, FL 32583; (850) 983-5216, Ext. 103; jlgibson@ifas.ufl.edu .

The authors thank the Fred C. Gloeckner Foundation for grant support, Smithers-Oasis for the propagation medium, Hatchett Creek Farms for plant material and Quality Analytical Laboratories for tissue analysis.