How To Revitalize Your Garden With NPK Fertilizer

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Beans and a few other plants add nitrogen to garden soil, but most extract this nutrient, as well as phosphorous and potassium, because these chemical elements are essential for survival. Nitrogen is part of the chlorophyll that helps plants convert sunlight into food and gives them their signature green hue. Phosphorous is important for cell division, root growth, and coping with stressors such as cold temperatures. Potassium is linked to higher crop yields and better disease resistance. When soil is deficient in one or more of these nutrients, plants become susceptible to disease. They may also communicate their displeasure with scorched-looking leaves, yellowing foliage, or stunted growth. NPK can restore these three nutrients when they become depleted, helping your plants survive and thrive.

NPK contains a balanced blend of nitrogen, phosphorous, and potassium. Some varieties are designed to make lawns lush and healthy, while others are ideal for flower gardens and vegetable patches. However, it's important to know if your soil is low in any of these nutrients before applying NPK fertilizer, or your plants might overdose on one or more of these nutrients. This causes nearly as many problems as inadequate nutrition. For example, too much nitrogen can prevent tomato plants from producing flowers and fruit. 

You can tell if your soil is lacking nitrogen by using a soil test kit such as the GiftBag 2-in-1 complete soil test kit for pH and nitrogen. Or get a kit that tests for nitrogen, phosphorous, and potassium. One option is the Leaping Lynx complete soil test kit, which also measures the pH level of your soil.

NPK fertilizer is available in a few different formulations. Granules deposit nutrients gradually, which works well for plants with lengthy growing seasons. Liquid fertilizers are poured or sprayed, while water-soluble varieties are added to water prior to application. Both deliver nutrients quickly, so they're often ideal for plants with short growing seasons. You can fertilize young plants with water-soluble fertilizer in the spring, then switch to a granular variety as they mature.

When comparing different NPK fertilizers, you'll see three numbers printed on each package. These represent the percentages of nitrogen, phosphorous, and potassium inside — in that order. For example, 10-10-10 means that each of these elements makes up 10% of the fertilizer. In contrast, 10-20-10 has a higher proportion of phosphorous. This variety is made for flowers and vegetables in the blossom-producing stage of their life cycle. NPK fertilizer with a higher percentage of nitrogen is ideal for grass and leafy greens, as well as plants early in their development, while types with higher potassium content are typically used to promote drought tolerance and disease resistance.

Some gardeners have reconsidered using synthetic fertilizers such as Miracle-Gro after learning that they can disrupt soil's microbial balance. Specifically, synthetic NPK fertilizer can discourage nitrogen-producing bacteria from colonizing the soil while encouraging an overabundance of nitrogen-consuming bacteria. Over time, this can harm the soil's structure. If this is a concern, opt for nutrient-rich compost and organic, slow-release NPK fertilizers. These include seaweed-derived liquids such as FoxFarm Bushdoctor Kelp Me Kelp You fertilizer and bone meal products such as Burpee organic bone meal fertilizer.

Applying NPK fertilizer to your garden is a straightforward process, and there are several ways to do it. One of the most common is broadcasting or dispersing fertilizer across your garden as uniformly as possible. This can be done before sowing seeds or while plants are well into their growth phase. A granule-broadcasting tool such as the Scotts Turf Builder EdgeGuard Mini Broadcast Spreader can make this process efficient, whether you're fertilizing a small garden or a large yard. 

Prefer to give your plants liquid nutrition? You can spray many liquid and water-soluble NPK fertilizers onto plants' leaves, a method known as foliar feeding. This is one of the fastest ways to perk up plants showing signs of nutrient deficiency. Water-soluble fertilizers are also a good match for drip irrigation systems. Just be sure not to over-fertilize, which can burn your plants' leaves. If this happens, watering the plant thoroughly and snipping damaged sections may help.

For plants that need extra nutrition at different points in their lifecycle, consider top dressing or side dressing. One popular top-dressing method is putting fertilizer on the soil near the bottom of an established plant. Side dressing, on the other hand, involves placing fertilizer on each side of a plant, approximately 4 inches from the stalk. It's typically applied in lines, beside rows of crops on farms and large garden plots. No matter how you apply your fertilizer, make sure to follow the manufacturer's instructions. This helps keep both you and your plants safe.