I need help with my science fair project?

Question

Topic Sentence:
Does earth’s gravity affect plant growth?
Hypothesis:
I think the earth’s gravity will affect the plant growth by forcing the plant’s stems to go upwards, away from the earth’s core, and the seeds reaching towards the earth’s core; because that is how they usually grow.

I have three weeks, so I cannot grow my own little plants, I'll have to buy three pre-grown plants.
But I'm still not sure.

My question is:
How can I "flip" the plants, so they are not standing upright like they usually are, with having the soil and seeds falling out of the see-through plastic cups?

Answer 1

get 2 plastic cups and make a whole for the stem to go out of and stick em together?

Answer 2

If you're going to use plants that are already growing, put a few pieces of plastic wrap around the stem so they overlap, then put a rubber band around the pot to hold the plastic in place.

If you used seeds from mustard, radishes, or beans (like lima beans) these would germinate within a week.

I'd also change "seeds" (as in "seeds reaching towards the Earth's core") to "roots". The seeds themselves don't move, unless they are stuck to the cotyledons of the plant as it grows.