While watering plants with water is a regular recommendation for most gardeners, there are special boosts that plants can enjoy from the rain.

Although strong winds and rain can damage a garden, rain during thunderstorms can be particularly beneficial for plants. This is because lightning adds nitrogen to a garden.

Plants crave nitrogen for a number of reasons; one is to produce chlorophyll, which is the green pigment in plants responsible for photosynthesis. If plants are nitrogen-deficient, they tend to look yellowish. Very low nitrogen levels for extended periods can result in stunted, sick, or dead plants.

Nitrogen makes up about 78 percent of the atmosphere but are not directly accessible to plants. To make up for this, plants get nitrogen from other sources which scientists prefer to as nitrogen fixation.

Alternative sources include fertilizers, the decomposition of organic matter in the soil, and organisms that can breakdown atmospheric nitrogen into something usable.

Plants can also get their nitrogen from high-energy processes in the atmosphere such as solar radiation and lightning.

The large amounts of heat and pressure that lightning generates provides enough energy to convert atmospheric nitrogen into a number of reactive nitrogen species which when mixed with water and oxygen in the atmosphere, resulting in rainfall that contains greater levels of nitrate and ammonium.

Once the rain hits the ground, they deposit ammonium and nitrates that plants can use, while bacteria and fungi in the soil can further transform the available nitrogen in a process called nitrification.

In comparison with tap water, which is more alkaline (higher in pH) or saltier (higher ionic strength) that others, prolonged watering with higher levels of chloride can also stop the plant from taking up available nitrate.

Plants can also be surprisingly harmed by high levels of sodium in some drinking water supplies.

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