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Understanding Soil Nutrients

Great tasting garden vegetables require the soil to have adequate amounts of the three primary macronutrients, which include nitrogen, potassium, and phosphorous. Each of these elements plays a crucial role in any plants biology. For example, nitrogen (N) is required for stem and leaf growth, and virtually every “green” part of the plant. Potassium (K) is used primarily  for the growth of roots, but also plays a role in the conversion of sunlight to  growth energy. Phosphorous (P) is used to by the plant during seed germination and flowering. Making sure your garden soil contains these primary nutrients is a crucial step when growing a successful vegetable garden.

The Role of Nitrogen in Soil

Nitrogen is one of the most abundant elements on our planet and is crucial to all forms of life. The periodic table of elements signifies nitrogen by the letter N. Fertilizer manufacturers will list N on their packaging to indicate nitrogen is included in the mix. Nitrogen is the element that gives your plants their green color. It is important in for many different biological processes within all plant life, and thus the most important soil nutrient for vegetable gardeners to be aware of.

Signs of Nitrogen Deficiency

Nitrogen is essential to growing healthy green plants. The most common signs of a nitrogen deficiency is yellowing and  browning of leaves. The overall growth of the plants may also be stunted if nitrogen is lacking in the soil. If you have a vegetable plant in this condition it is recommended that you test the soil first, then add fertilizer as necessary. Typically, soil that is low in nitrogen will require 2 to 5 pounds of fertilizer for every 100 square feet of surface area. Alternative, you can add manure, fish meal, or blood meal to as an organic source of nitrogen for your garden.

Signs of Too Much Nitrogen

Too much nitrogen can also cause problems in a vegetable garden, so it is important to use caution when adding fertilizer to your soil. If your plant is absorbing too much nitrogen from the soil it may produce thin and gangling leaves. The plants may appear to have a healthy green color, but fail to produce any fruit. If you discover too much nitrogen in the soil it is recommended that you grow leafy green veggies that require high amounts of nitrogen and do not produce large fruit. Some good options would be Swiss chard, spinach, lettuce, or virtually any leafy green.

The Role of Potassium in Soil

Just as in human nutrition, potassium plays an very important role in the biology of plants. Potassium is abundant in the roots and buds of vegetable plants. Most importantly, it  is one of the contributing factors to vegetable flavor. Making sure that potassium levels are high in your soil will ultimately lead to better tasting fruits and vegetables. Potassium is found on the periodic table of elements under letter K.

Signs of Potassium Deficiency

Common signs of potassium deficiency will be browning on the veins of the plant and browning underneath the leaves. It can be hard to diagnose in many cases, so it is best to test your soil once per year to make sure potassium levels are always adequate. If you discover low potassium levels in soil, adding 5 to 10 pounds of fertilizer per 100 square feet should do the trick. Potash, greensand, and wood ash are the most common sources of potassium for vegetable gardeners.

The Role of Phosphorous in Soil

Phosphorous, periodic symbol P, is important during the early stages in a plants life. Seed germination depends partly on phosphorous, so it is ideal to have this nutrient abundant if you are propagating your vegetables from seeds. It is still necessary to plants later in life and plays a role in the flowering of vegetables. Also, it is needed by a plant to produce a strong effective root system.

Signs of Phosphorous Deficiency

If your soil is deficient in Phosphorus the leaves of the plant may show a blue, violent, or purple tint. Also, you may notice slowed growth and small withering plants. Organic gardeners can add natural phosphorus sources to the soil or simply standard fertilizer. as a remedy. Bone meal, fish emulsion, and rotten manure are common sources of phosphorus.

Too Much Potassium or Phosphorous?

It is very uncommon for too much of either of these elements to be present in soil. High levels of potassium or phosphorous in soil is unlikely to cause an adverse effects on your vegetable garden.

The Role of Calcium in Soil

In humans, calcium is essential to building strong bones. In plants, calcium is essential for in the cellular wall structure and provides water retention in the plants cells. Calcium can be supplied to your plants via dolomite limestone or gypsum. Calcium is also present in certain types of fertilizer.

The Role of Magnesium in Soil

Magnesium is important during the growth stages of your garden. It is one of the elements that makes up chlorophyll, thus is essential to the conversion of sunlight into energy. The best way to keep your soil with healthy levels of magnesium is via organic material and fertilizer. Producing organic compost is our recommendation.

The Role of Sulfur in Soil

The primary role of sulfur in the soil is the production of proteins. It is also needed to produce thick healthy roots. Proteins are needed to sustain strong healthy plants. Plants lacking sulfur in the soil will have less resistance to cold weather.

Trace Elements or Micronutrients

The elements listed below are found in small concentrations, but are important to healthy plant growth. You can ensure these trace elements are present in the soil by using organic compost in your soil.

  • Zinc
  • Boron
  • Iron
  • Manganese
  • Copper
  • Chloride
  • Molybdenum

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