When are scientific claims accepted? and when are they questioned and/or rejected?

The answer is;  When the scientific claims are accepted when they are corroborated by scientific data. Experiments are set to collect data and make observations regarding the claims. Based on the outcome, the claims (which will be formulated as a hypothesis) will be accepted or rejected. When the experiment is replicated by different independent scientists and producing predictable results, then the claims become a scientific fact.

1: most common garden plants prefer loam — soils with a balance of different-sized mineral particles (approximately 40% sand, 40% silt, and 20% clay) with ample organic matter and pore space. however, some plants grow better in sandy soils, while others are well-adapted to clay soils.

2: available water capacity is the maximum amount of plant available water a soil can provide. it is an indicator of a soil's ability to retain water and make it sufficiently available for plant use. available water capacity is the water held in soil between its field capacity and permanent wilting point.

3: it is the same for all living things (plants and animals). it also includes very tiny organisms that our eyes cannot see. they are known as microorganisms, and include viruses, bacteria and fungi.