Question 1

What does NPK mean on fertilizer labels?

Accepted Answer

NPK stands for Nitrogen (N), Phosphorus (P), and Potassium (K), the three primary nutrients plants need. The three numbers on a fertilizer bag (like 10-10-10) represent the percentage by weight of each nutrient. Nitrogen promotes leafy growth, phosphorus supports root development and flowering, and potassium strengthens overall plant health and disease resistance. A 10-pound bag of 10-10-10 contains 1 pound each of N, P, and K.

Question 2

What is the difference between organic and synthetic fertilizer?

Accepted Answer

Organic fertilizers (compost, bone meal, fish emulsion) come from natural sources and release nutrients slowly as soil microbes break them down. They improve soil structure over time but are less precise in nutrient content. Synthetic fertilizers are manufactured to deliver exact nutrient ratios quickly, but they do not improve soil biology and can cause salt buildup with overuse. Many gardeners use a combination of both for best results.

Question 3

How often should I fertilize my vegetable garden?

Accepted Answer

It depends on the crop. Heavy feeders like tomatoes, corn, and squash benefit from feeding every 2 to 3 weeks during the growing season. Medium feeders like peppers and beans need fertilizer every 3 to 4 weeks. Light feeders like carrots, beets, and herbs may only need one application at planting. Always follow package rates and reduce fertilizing as harvest approaches.

Question 4

What is a soil test and why should I get one?

Accepted Answer

A soil test analyzes your soil's nutrient levels, pH, and organic matter content. It tells you exactly what your soil needs instead of guessing. Your local cooperative extension office usually offers soil tests for $10 to $25. Test results come with specific fertilizer recommendations for your crops. Test in fall or early spring before the growing season. Without a test, you risk over-applying nutrients that are already adequate.

Question 5

What are the signs of over-fertilizing?

Accepted Answer

Common signs include leaf burn (brown, crispy edges), excessive leafy growth with few flowers or fruit, white salt crust on the soil surface, wilting despite adequate water, and yellowing or dropping of lower leaves. Over-fertilizing can also damage beneficial soil microbes. If you suspect over-fertilization, flush the soil with deep watering and hold off on further feeding for several weeks.

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