Will coffee kill plants?

Hint:
- The residue of brewing coffee is coffee grounds, which are the final product after the preparation of coffee.
- Used coffee grounds are usually considered waste and are discarded or composted. But it does have certain uses.

Complete answer:
- Caffeine affects plants growth:
 N-methyltransferases, which are found in all plants and build a variety of compounds, are the enzymes that create caffeine. When coffee leaves fall to the ground, they contaminate the soil with caffeine, which prevents other plants from germinating, reducing competition. This means that too much caffeine can be harmful to plant growth.
- caffeine is a chemical stimulant and it increases the biological process of humans as well as plants. Such as photosynthesis and absorbing water and nutrients from the soil. The pH of the soil is also lowered. The increase in acidity can be toxic to some plants but some enjoy it for example blueberries.
- Caffeine studies on plants have shown that cell growth rates are initially stable, but that the caffeine quickly kills or distorts these cells, resulting in a dead or stunted plant.
- Potassium (11.7 g/kg), magnesium (1.9 g/kg), and phosphorus (1.8 g/kg) are all present in high concentrations in dry coffee grounds. Worms and acid-loving plants like blueberries love them, even though they normally have a neutral pH due to acids leached from the grounds during use.
- Coffee grounds can be composted or used as mulch in gardens because they slowly release nitrogen into the soil. Coffee grounds are especially useful as a soil amendment.

Note:
- Coffee is the world's second most traded commodity, trailing only crude oil in terms of volume consumed.
- Coffee was banned in Mecca in 1511, just a few years after its introduction to Ethiopia. It was thought to promote radical thinking as well as idleness.
- Arabica coffee is named after the Arabian Peninsula, where it was first grown. Robusta coffee is a more hardy plant, but it contains twice as much caffeine as Arabica coffee.