Questions: Garden and Planting Basics

Question 1

A gardener's tomato plants are yellowing and producing almost no fruit despite weekly fertilizer applications. The plants are in a bed that gets only 2 hours of sunlight per day. What is most likely causing the problem and what should the gardener do?

• A. The plants need more fertilizer — increase the application rate for better nutrient uptake
• B. The plants are overwatered — reduce watering frequency to once per week
• C. The plants lack adequate sunlight — tomatoes need 6–8 hours of direct sun, and no amount of fertilizer compensates for insufficient photosynthesis
• D. The soil needs more compost to improve drainage and nutrient availability

Answer: (C)

Sun is a biological requirement, not an aesthetic preference. Tomatoes need 6–8 hours of direct sunlight for photosynthesis; without it, they cannot produce the energy for fruit regardless of soil nutrition. Fertilizer feeds healthy, photosynthesizing plants — it cannot substitute for light. This is the core principle: match the plant to the conditions, or no input will rescue it.

Question 2

A gardener in USDA Zone 5 wants to plant a flowering shrub that will return each spring. Which factor is most important when selecting the shrub at the nursery?

• A. Whether the shrub's bloom color matches the garden's existing color palette
• B. Whether the shrub is rated hardy to Zone 5 or a colder zone, so it will survive winter minimum temperatures
• C. Whether the shrub performed well in the nursery's climate-controlled greenhouse
• D. Whether the shrub was grown using organic methods

Answer: (B)

Hardiness zone rating is the primary filter for any perennial plant. A shrub rated only to Zone 7 will die in a Zone 5 winter no matter how healthy it looks at purchase. The USDA zone map exists precisely for this decision: it encodes whether a plant's biological cold tolerance matches your climate. Greenhouse performance is meaningless; what matters is survival through your winter minimum.

Question 3

When a garden plant is wilting or struggling, increasing watering frequency is usually the safest and most effective first response.

• T. True
• F. False

Answer: False

Overwatering is the most common cause of plant failure, not underwatering. Wilting can be caused by either too little or too much water — overwatered roots rot and lose their ability to take up water, causing the same wilting symptom as drought. The correct diagnosis is to check soil moisture (push a finger an inch into the soil) before adding more water. Reflexively watering a struggling plant often makes the problem worse.

Question 4

Adding compost to garden soil improves both clay soil (which drains too slowly) and sandy soil (which drains too quickly), moving both toward better growing conditions.

• T. True
• F. False

Answer: True

Compost improves soil structure in both directions: in clay, it opens up the dense matrix to improve drainage and root penetration; in sand, it adds organic matter that retains water and nutrients longer. This makes compost the universal soil amendment — not because it's magic, but because it moves almost any soil toward the loamy middle ground that most plants prefer.

Question 5

Why do most garden plants benefit from deep, infrequent watering rather than frequent shallow watering?

Model answer: Deep watering pushes moisture deep into the soil, encouraging roots to grow downward to reach it. This produces a deeper root system that can access moisture even during dry spells, making plants more drought-tolerant. Frequent shallow watering keeps moisture near the surface, so roots stay shallow. Shallow-rooted plants are more vulnerable to heat and drought and require constant attention to survive.

The practical implication: water less often but more thoroughly, and check moisture by probing an inch into the soil rather than watering on a fixed schedule. This single habit reduces overwatering, encourages deeper roots, and makes plants more resilient — and it applies equally to lawns, vegetable gardens, and container plants.