Gels and powders are primarily used directly after taking cuttings, usually by immediately dipping the cut end into the gel or powder before transplanting. Solutions, compounds, and concentrates are typically made to mix with water in either your nutrient solution or can be sprayed or misted directly on your clones as a foliar spray. Typically cloning gels and solutions are a combination of vitamins and hormones to reduce transplant shock and protect from bacteria and fungi, and root stimulators to encourage healthy root growth.