NYC Horticulturist Exam Questions With
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. Which soil texture generally provides the best balance of drainage
and nutrient retention for most landscape plants?
A. Sand
B. Silt
C. Clay
D. Loam
Correct Answer: D
Loam contains a balanced mixture of sand, silt, and clay, allowing
adequate drainage while retaining moisture and nutrients essential for
plant growth.
2. The primary function of nitrogen in plant growth is to promote:
A. Root development
B. Flower production
C. Leaf and stem growth
D. Disease resistance
,Correct Answer: C
Nitrogen is a key component of chlorophyll and proteins, making it
essential for vigorous vegetative (leaf and stem) growth.
3. Which pH range is generally optimal for most ornamental plants?
A. 3.5–4.5
B. 5.5–7.0
C. 7.5–8.5
D. 8.5–9.5
Correct Answer: B
Most ornamental plants prefer slightly acidic to neutral soil, which
allows maximum nutrient availability.
4. Mulching around plants primarily helps to:
A. Increase soil compaction
B. Reduce soil temperature fluctuations
C. Eliminate the need for watering
D. Prevent photosynthesis
Correct Answer: B
Mulch moderates soil temperature, conserves moisture, and suppresses
weeds, creating a more stable root environment.
5. Which pruning method removes the entire branch at its point of
origin?
, A. Heading
B. Thinning
C. Shearing
D. Pinching
Correct Answer: B
Thinning cuts remove branches at their origin, improving light
penetration and air circulation without stimulating excessive regrowth.
6. The best time to prune spring-flowering shrubs is:
A. Late winter before buds form
B. During peak flowering
C. Immediately after flowering
D. In mid-summer
Correct Answer: C
Spring-flowering shrubs bloom on old wood, so pruning after flowering
preserves next year’s buds.
7. Which plant part is primarily responsible for water absorption?
A. Leaves
B. Stems
C. Flowers
D. Roots
, Correct Answer: D
Roots absorb water and nutrients from the soil and anchor the plant.
8. Transpiration in plants refers to the:
A. Uptake of carbon dioxide
B. Loss of water vapor through leaves
C. Movement of sugars to roots
D. Absorption of sunlight
Correct Answer: B
Transpiration is the evaporation of water from leaf surfaces, aiding
nutrient transport and temperature regulation.
9. Which fertilizer number represents phosphorus?
A. First
B. Second
C. Third
D. Fourth
Correct Answer: B
In fertilizer labels (N–P–K), phosphorus is always the second number and
supports root and flower development.
10. A biennial plant completes its life cycle in:
A. One growing season
B. Two growing seasons
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. Which soil texture generally provides the best balance of drainage
and nutrient retention for most landscape plants?
A. Sand
B. Silt
C. Clay
D. Loam
Correct Answer: D
Loam contains a balanced mixture of sand, silt, and clay, allowing
adequate drainage while retaining moisture and nutrients essential for
plant growth.
2. The primary function of nitrogen in plant growth is to promote:
A. Root development
B. Flower production
C. Leaf and stem growth
D. Disease resistance
,Correct Answer: C
Nitrogen is a key component of chlorophyll and proteins, making it
essential for vigorous vegetative (leaf and stem) growth.
3. Which pH range is generally optimal for most ornamental plants?
A. 3.5–4.5
B. 5.5–7.0
C. 7.5–8.5
D. 8.5–9.5
Correct Answer: B
Most ornamental plants prefer slightly acidic to neutral soil, which
allows maximum nutrient availability.
4. Mulching around plants primarily helps to:
A. Increase soil compaction
B. Reduce soil temperature fluctuations
C. Eliminate the need for watering
D. Prevent photosynthesis
Correct Answer: B
Mulch moderates soil temperature, conserves moisture, and suppresses
weeds, creating a more stable root environment.
5. Which pruning method removes the entire branch at its point of
origin?
, A. Heading
B. Thinning
C. Shearing
D. Pinching
Correct Answer: B
Thinning cuts remove branches at their origin, improving light
penetration and air circulation without stimulating excessive regrowth.
6. The best time to prune spring-flowering shrubs is:
A. Late winter before buds form
B. During peak flowering
C. Immediately after flowering
D. In mid-summer
Correct Answer: C
Spring-flowering shrubs bloom on old wood, so pruning after flowering
preserves next year’s buds.
7. Which plant part is primarily responsible for water absorption?
A. Leaves
B. Stems
C. Flowers
D. Roots
, Correct Answer: D
Roots absorb water and nutrients from the soil and anchor the plant.
8. Transpiration in plants refers to the:
A. Uptake of carbon dioxide
B. Loss of water vapor through leaves
C. Movement of sugars to roots
D. Absorption of sunlight
Correct Answer: B
Transpiration is the evaporation of water from leaf surfaces, aiding
nutrient transport and temperature regulation.
9. Which fertilizer number represents phosphorus?
A. First
B. Second
C. Third
D. Fourth
Correct Answer: B
In fertilizer labels (N–P–K), phosphorus is always the second number and
supports root and flower development.
10. A biennial plant completes its life cycle in:
A. One growing season
B. Two growing seasons
