Question

The difficulties encountered in a roof garden are as follows
(A). Soil depth is limited
(B). Large trees and shrubs can be grown with greater ease than any other garden
(C). Drainage needs to be ensured
(D). Frequent watering is required
Choose the correct answer from the options given below:

• A. (A), (B) and (D) only.
• B. (A), (B) and (C) only.
• C. (A), (C) and (D) only.
• D. (B), (C) and (D) only.

Hint:

When thinking about rooftop gardening, always consider the two biggest constraints: weight and water. Limited weight capacity restricts soil depth and plant size. Exposure to elements increases water needs and necessitates excellent drainage.

Answer 1

The Correct Option is C

Step 1: Understand the Goal:
Identify the real challenges of creating and maintaining a roof garden.

Step 2: Analysis:
Let's examine each statement:
\[\begin{array}{rl} \bullet & \text{(A) Soil depth limitations: This is a major challenge. Roofs have weight restrictions, so only a thin layer of light growing material can be used, limiting plant choices. This is a difficulty. } \\ \bullet & \text{(B) Large trees and shrubs are easily grown: This is incorrect. The limited soil and weight constraints make growing large trees and shrubs very difficult, if not impossible. } \\ \bullet & \text{(C) Drainage is essential: This is a key difficulty. Proper drainage prevents water damage to the building and root rot. This is a difficulty. } \\ \bullet & \text{(D) Frequent watering is necessary: This is a significant challenge. The shallow soil dries out quickly due to sun and wind exposure, requiring more frequent watering compared to ground-level gardens. This is a difficulty. } \\ \end{array}\]The challenges are (A), (C), and (D).

Step 3: Conclusion:
The correct answer, listing only the difficulties, is (A), (C) and (D).