You probably thought fertilising your garden is pretty simple – you just pour a bunch of it around the plants, and then water it in. It’s not that easy and should never be done this way.
First, do your plants need fertilizer at all?
Most plant problems can’t be solved by fertilizer. Pay attention to the soil. Add organic materials like compost regularly to improve soil drainage, tilth and nutrition.
We have said it before and we will say it again: never fertilize your lawn or garden without first performing a test. Most soils are fertile enough to support most plants, especially when compost is regularly added. When soil is properly cared for in the perennial garden, where roots are deep, fertilizer may not be needed. (I don’t recall the last time I fertilized the flower beds.
Plants require 18 essential nutrients to grow and thrive. Air and water provide the most carbon, hydrogen, and oxygen. The next 6 nutrients are considered macronutrients;…Nitrogen, Phosphorus, and Potassium…. Calcium, Magnesium and Sulfur. The nine remaining elements are micronutrients, including Chloride (iron), Boron (manganese), Zinc, Copper, Molybdenum (nickel), and Cobalt… They all play a role in different plant structures and functions… If one essential nutrient deficiency occurs, plant growth may be poor, even if other essential nutrients are plentiful. These nutrients are primarily found in the soil. However, when soil nutrient reserves begin to diminish, they can be added through fertilizer, manure, or compost.
Fertility should be checked on vegetable gardens every two years. There may be a need to add nitrogen in veggie gardens due to the high turnover. However, this is rare. The need for fertilizers will be rare if you use basic crop rotation, mulching, and legume cover crops. Growing vegetables or flowers in a container will require regular fertilization.
Fertility may not be a problem just because your leaves are yellowing or small, you have late flowering or that they “look” like they need fertiliser. soil pH , soil drainage, weather conditions and temperature, as well as soil alkalinity , can all affect a plant’s development. Fertilizer won’t solve any of these problems.
What are the problems if I fertilize my garden when it doesn’t require it?
The majority of commercial fertilizers are heavy in nitrogen ( , the first letter on the NPK bag). If you fertilize too much with nitrogen, the plant will produce a lot more top growth and have fewer fruits and roots. You can also end up with no fruit or roots. According to Colorado State University Extension, too much nitrogen can cause insect and diseases problems. soils may require regular fertilizer applications. A soil test will be necessary to determine how much fertilizer should be applied.GMO Definition: Official Definition You Will Be Surprised
Too much fertilizer can also cause water pollution. The phosphorous that plants don’t use is washed into the local waterways, rivers, lakes, and oceans by rain. It can cause problems such as algal blooms, which choke marine life. It may seem impossible that one gardener could make a significant difference, but multiply the number of gardeners in a region by the amount of fertilizer being run off from farms to see how serious this problem is. Every action counts.
Too little phosphorus may also cause chlorosis (a yellowing of the leaf tissue) and can kill mycorrhizal fungal that plants need. Mycorrhizal mushrooms are essential to the plant’s ability to absorb iron and other micronutrients.
Nitrogen (N), potassium (K) and phosphorus are the three nutrients that vegetables require most. Iron, copper, manganese, and zinc, as well as other nutrients, are required in smaller quantities. Most of these nutrients, with the exception of phosphorus and nitrogen, are available in soils at sufficient or excessive levels. Addition of nutrients that aren’t needed can lead to deficiencies in other nutrients or an imbalance. No one can tell you exactly what your soil needs without the help of a soil analysis conducted by a laboratory.Fertilizing Vegetable Garden at Colorado State University Extension.
When should I not fertilize my garden
Avoid fertilizing with granular fertiliser before heavy rains, as most of it will wash away.
Don’t fertilize if you have had dry weather for a while, or if there is a drought. It could do more harm than it does good. When the plant is under heat stress , it may slow down its process when water is limited.
Wait until the soil has completely dried out before you fertilize if your area has recently been flooded, or experienced heavy rain.
When plants are dormant they won’t need or use the nutrients. The fertilizer is washed off before the plant can use it.
Fertilizing plants heavily at a young age can lead to a “leggy” appearance – a plant with a lot of stems and thin growth on top, and a root system that is too small to support future growth or fruit.
How to apply fertilizer properly
When preparing a bed for spring planting you should spread the recommended amount of fertilizer evenly across the whole garden bed. With the back of a garden rake, work it into the soil’s top three inches. Water it gently to help the fertilizer penetrate the soil. Add granular fertilizer to the soil a few weeks before you plan to plant. This gives the soil microbes the time they need for it be converted into a chemical that the plants can utilize.
Sidedressing is another way to fertilize your plants. Apply the fertilizer 6 inches apart from the row you want to plant or underneath the roots. You should make sure that the roots of the seedlings are not in direct contact with fertilizer. Otherwise, they could be burnt. This becomes less important as the plant grows.
Add granular fertiliser around the roots of the plant if you have already planted. Use a cultivator, hand trowel or any other gardening tool to gently work the fertilizer into the soil. Do not disturb the roots. Instead, work the fertilizer in 2 inches deep. The plant may be burned if the fertilizer comes into contact with its stem or leaves. After you have worked it in, water the soil gently.
Compost adds organic matter and nutrients to the soil, which is a great way to fertilize. Compost needs time to decompose – usually a few weeks. You should therefore add compost in the spring and fall at a thickness of 2 inches. Add it to the soil after planting as a mulch. Spread it out around the root zone another 2 inches, but don’t touch seedlings. Compost does not need to be worked into the soil as bacteria, insects, and other microbes will do it for you.
What is the difference between liquid and granular fertilizer?
Liquid fertilisers make nutrients instantly available to plants. If a soil analysis indicates that liquid fertilizers will be needed immediately, then this is the best option. Granular fertilizers need time to decompose in the soil and become usable. It is best to apply them early in the growing season, before or during planting.
Resources: Does fertilizer help or harm plants? University of Minnesota Extension. Starting a Garden – Fertilization. University of Illinois Extension. Fertilizing the Vegetable Garden. Colorado State University Extension. Different ways to apply commercial fertilizer and compost. University of Saskatchewan.
familyservicehub 
