Question

ASAP HELP WITH HYPOTHESIS: Many plants can affect the growth of other plants near them. This can occur when one plant produces a chemical that affects another plant.
Create a hypothesis to determine if a solution containing ground-up goldenrod plants has an effect on the growth of radish seedlings.

Answer 1

Your hypothesis could be:
When planting the ground-up goldenrod plants next to the radish seedlings, I predict that the chemical coming out of the goldenrods, will choke out the oxygen and the carbon dioxide that the seedlings need to grow and thrive.