NYC HORTICULTURIST
EXAM PREPARATION
2026/2027 • 150 Original Practice Questions & Answers
Horticulture • Plant Health • Urban Forestry • Green Infrastructure
STUDY GUIDE NOTE
Independent learning resource with original practice questions. Not an official NYC DCAS question bank and does not reproduce
official exam questions.
Introduction
This guide strengthens practical horticultural knowledge through questions, answers, and rationales across soil science, plant
identification, propagation, plant health, maintenance, urban forestry, green infrastructure, and professional judgment.
Important official-exam distinction: NYC DCAS’s Notice of Examination for Administrative Horticulturist, Exam No. 6005, describes
an Education and Experience Exam (EEE), with scoring based on education and qualifying work experience. This multiple-choice guide
is supplementary subject-matter practice—not a representation of the official DCAS exam format.
Attempt each question before reading its answer, review the rationale, and verify current requirements directly with DCAS.
Contents & Practice Domains
• 1. Soil Science, Fertility & Plant Nutrition — 25 questions
• 2. Plant Identification, Biology & Selection — 25 questions
• 3. Propagation, Planting & Establishment — 25 questions
• 4. Plant Health, Pests & Integrated Pest Management — 24 questions
• 5. Pruning, Landscape Maintenance & Safety — 25 questions
• 6. Urban Forestry, Green Infrastructure & Professional Practice — 25 questions
• 7. Applied Scenarios & Professional Judgment — 1 question
NYC Horticulturist Exam Prep • Independent Practice Guide Page 1
,1. Soil Science, Fertility & Plant Nutrition
Question 1
What does soil pH indicate?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. The acidity or alkalinity of the soil solution.
Correct Answer: D. The acidity or alkalinity of the soil solution.
Rationale: A pH value reflects hydrogen-ion activity; it helps guide plant selection and amendment decisions.
Question 2
Which soil texture generally balances drainage and water-holding capacity well?
A. It removes the need to follow product directions
B. It should be done without authorization
C. Loam.
D. It is determined only by appearance
Correct Answer: C. Loam.
Rationale: Loam contains a useful mixture of sand, silt, and clay, though structure and organic matter also matter.
Question 3
Which nutrient is most associated with leafy vegetative growth?
A. It should be done without checking site conditions
B. Nitrogen.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. Nitrogen.
Rationale: Nitrogen is part of chlorophyll, amino acids, and proteins and supports vegetative growth.
Question 4
Which nutrient is especially important for energy transfer and root development?
A. Phosphorus.
B. It guarantees identical results for every species
C. It eliminates the need for inspection or records
D. It should replace the applicable safety procedure
Correct Answer: A. Phosphorus.
Rationale: Phosphorus is part of ATP and nucleic acids and supports root growth and reproductive development.
Question 5
Which nutrient helps regulate stomatal function and water relations?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. Potassium.
Correct Answer: D. Potassium.
Rationale: Potassium supports osmotic regulation, enzyme activity, and stress tolerance.
NYC Horticulturist Exam Prep • Independent Practice Guide Page 2
,Question 6
Why test soil before applying fertilizer?
A. It removes the need to follow product directions
B. It should be done without authorization
C. To determine pH and nutrient status so amendments can be targeted.
D. It is determined only by appearance
Correct Answer: C. To determine pH and nutrient status so amendments can be targeted.
Rationale: Testing reduces guesswork and helps prevent unnecessary applications and nutrient runoff.
Question 7
What is a common symptom of nitrogen deficiency?
A. It should be done without checking site conditions
B. Yellowing that often begins on older leaves, with reduced growth.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. Yellowing that often begins on older leaves, with reduced growth.
Rationale: Nitrogen is mobile within plants, so the plant can move it from older leaves to newer growth.
Question 8
What is the main purpose of adding mature compost to soil?
A. To improve soil structure and contribute organic matter.
B. It guarantees identical results for every species
C. It eliminates the need for inspection or records
D. It should replace the applicable safety procedure
Correct Answer: A. To improve soil structure and contribute organic matter.
Rationale: Organic matter can improve aggregation, water retention, and biological activity.
Question 9
What is soil compaction likely to reduce?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. Pore space, aeration, and infiltration.
Correct Answer: D. Pore space, aeration, and infiltration.
Rationale: Compaction compresses soil pores, restricting root growth and the movement of air and water.
Question 10
What does a soil test recommendation help determine?
A. It removes the need to follow product directions
B. It should be done without authorization
C. Appropriate amendment type and application rate.
D. It is determined only by appearance
Correct Answer: C. Appropriate amendment type and application rate.
Rationale: Rates should be based on test results, plant needs, and product directions.
NYC Horticulturist Exam Prep • Independent Practice Guide Page 3
, Question 11
What is chlorosis?
A. It should be done without checking site conditions
B. Yellowing of normally green plant tissue.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. Yellowing of normally green plant tissue.
Rationale: Chlorosis may result from nutrient deficiency, unsuitable pH, waterlogging, root injury, or disease.
Question 12
Which amendment is commonly used to raise acidic soil pH?
A. Agricultural limestone, when recommended by a soil test.
B. It guarantees identical results for every species
C. It eliminates the need for inspection or records
D. It should replace the applicable safety procedure
Correct Answer: A. Agricultural limestone, when recommended by a soil test.
Rationale: Limestone neutralizes acidity; the amount needed depends on soil characteristics and target pH.
Question 13
Which amendment may be used to lower soil pH in suitable conditions?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. Elemental sulfur, when recommended.
Correct Answer: D. Elemental sulfur, when recommended.
Rationale: Microbial oxidation of sulfur can acidify soil over time; effectiveness depends on soil and conditions.
Question 14
Why should fertilizer not be applied immediately before heavy rain?
A. It removes the need to follow product directions
B. It should be done without authorization
C. Nutrients may wash off or leach away.
D. It is determined only by appearance
Correct Answer: C. Nutrients may wash off or leach away.
Rationale: Runoff and leaching waste fertilizer and can pollute waterways.
Question 15
What is the purpose of mulch around landscape plants?
A. It should be done without checking site conditions
B. To moderate soil temperature, conserve moisture, and suppress weeds.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. To moderate soil temperature, conserve moisture, and suppress weeds.
Rationale: Mulch also reduces erosion, but should not be piled against trunks or stems.
NYC Horticulturist Exam Prep • Independent Practice Guide Page 4
EXAM PREPARATION
2026/2027 • 150 Original Practice Questions & Answers
Horticulture • Plant Health • Urban Forestry • Green Infrastructure
STUDY GUIDE NOTE
Independent learning resource with original practice questions. Not an official NYC DCAS question bank and does not reproduce
official exam questions.
Introduction
This guide strengthens practical horticultural knowledge through questions, answers, and rationales across soil science, plant
identification, propagation, plant health, maintenance, urban forestry, green infrastructure, and professional judgment.
Important official-exam distinction: NYC DCAS’s Notice of Examination for Administrative Horticulturist, Exam No. 6005, describes
an Education and Experience Exam (EEE), with scoring based on education and qualifying work experience. This multiple-choice guide
is supplementary subject-matter practice—not a representation of the official DCAS exam format.
Attempt each question before reading its answer, review the rationale, and verify current requirements directly with DCAS.
Contents & Practice Domains
• 1. Soil Science, Fertility & Plant Nutrition — 25 questions
• 2. Plant Identification, Biology & Selection — 25 questions
• 3. Propagation, Planting & Establishment — 25 questions
• 4. Plant Health, Pests & Integrated Pest Management — 24 questions
• 5. Pruning, Landscape Maintenance & Safety — 25 questions
• 6. Urban Forestry, Green Infrastructure & Professional Practice — 25 questions
• 7. Applied Scenarios & Professional Judgment — 1 question
NYC Horticulturist Exam Prep • Independent Practice Guide Page 1
,1. Soil Science, Fertility & Plant Nutrition
Question 1
What does soil pH indicate?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. The acidity or alkalinity of the soil solution.
Correct Answer: D. The acidity or alkalinity of the soil solution.
Rationale: A pH value reflects hydrogen-ion activity; it helps guide plant selection and amendment decisions.
Question 2
Which soil texture generally balances drainage and water-holding capacity well?
A. It removes the need to follow product directions
B. It should be done without authorization
C. Loam.
D. It is determined only by appearance
Correct Answer: C. Loam.
Rationale: Loam contains a useful mixture of sand, silt, and clay, though structure and organic matter also matter.
Question 3
Which nutrient is most associated with leafy vegetative growth?
A. It should be done without checking site conditions
B. Nitrogen.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. Nitrogen.
Rationale: Nitrogen is part of chlorophyll, amino acids, and proteins and supports vegetative growth.
Question 4
Which nutrient is especially important for energy transfer and root development?
A. Phosphorus.
B. It guarantees identical results for every species
C. It eliminates the need for inspection or records
D. It should replace the applicable safety procedure
Correct Answer: A. Phosphorus.
Rationale: Phosphorus is part of ATP and nucleic acids and supports root growth and reproductive development.
Question 5
Which nutrient helps regulate stomatal function and water relations?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. Potassium.
Correct Answer: D. Potassium.
Rationale: Potassium supports osmotic regulation, enzyme activity, and stress tolerance.
NYC Horticulturist Exam Prep • Independent Practice Guide Page 2
,Question 6
Why test soil before applying fertilizer?
A. It removes the need to follow product directions
B. It should be done without authorization
C. To determine pH and nutrient status so amendments can be targeted.
D. It is determined only by appearance
Correct Answer: C. To determine pH and nutrient status so amendments can be targeted.
Rationale: Testing reduces guesswork and helps prevent unnecessary applications and nutrient runoff.
Question 7
What is a common symptom of nitrogen deficiency?
A. It should be done without checking site conditions
B. Yellowing that often begins on older leaves, with reduced growth.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. Yellowing that often begins on older leaves, with reduced growth.
Rationale: Nitrogen is mobile within plants, so the plant can move it from older leaves to newer growth.
Question 8
What is the main purpose of adding mature compost to soil?
A. To improve soil structure and contribute organic matter.
B. It guarantees identical results for every species
C. It eliminates the need for inspection or records
D. It should replace the applicable safety procedure
Correct Answer: A. To improve soil structure and contribute organic matter.
Rationale: Organic matter can improve aggregation, water retention, and biological activity.
Question 9
What is soil compaction likely to reduce?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. Pore space, aeration, and infiltration.
Correct Answer: D. Pore space, aeration, and infiltration.
Rationale: Compaction compresses soil pores, restricting root growth and the movement of air and water.
Question 10
What does a soil test recommendation help determine?
A. It removes the need to follow product directions
B. It should be done without authorization
C. Appropriate amendment type and application rate.
D. It is determined only by appearance
Correct Answer: C. Appropriate amendment type and application rate.
Rationale: Rates should be based on test results, plant needs, and product directions.
NYC Horticulturist Exam Prep • Independent Practice Guide Page 3
, Question 11
What is chlorosis?
A. It should be done without checking site conditions
B. Yellowing of normally green plant tissue.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. Yellowing of normally green plant tissue.
Rationale: Chlorosis may result from nutrient deficiency, unsuitable pH, waterlogging, root injury, or disease.
Question 12
Which amendment is commonly used to raise acidic soil pH?
A. Agricultural limestone, when recommended by a soil test.
B. It guarantees identical results for every species
C. It eliminates the need for inspection or records
D. It should replace the applicable safety procedure
Correct Answer: A. Agricultural limestone, when recommended by a soil test.
Rationale: Limestone neutralizes acidity; the amount needed depends on soil characteristics and target pH.
Question 13
Which amendment may be used to lower soil pH in suitable conditions?
A. It is always required regardless of circumstances
B. It has no effect on plant health or the environment
C. It should be repeated immediately without diagnosis
D. Elemental sulfur, when recommended.
Correct Answer: D. Elemental sulfur, when recommended.
Rationale: Microbial oxidation of sulfur can acidify soil over time; effectiveness depends on soil and conditions.
Question 14
Why should fertilizer not be applied immediately before heavy rain?
A. It removes the need to follow product directions
B. It should be done without authorization
C. Nutrients may wash off or leach away.
D. It is determined only by appearance
Correct Answer: C. Nutrients may wash off or leach away.
Rationale: Runoff and leaching waste fertilizer and can pollute waterways.
Question 15
What is the purpose of mulch around landscape plants?
A. It should be done without checking site conditions
B. To moderate soil temperature, conserve moisture, and suppress weeds.
C. It is unrelated to soil, water, or growing conditions
D. It always improves every plant at every site
Correct Answer: B. To moderate soil temperature, conserve moisture, and suppress weeds.
Rationale: Mulch also reduces erosion, but should not be piled against trunks or stems.
NYC Horticulturist Exam Prep • Independent Practice Guide Page 4
