Article V explains the amendment process, which is different and more difficult than the process for making laws. When two-thirds of the Senate and two-thirds of the House of Representatives vote to change the Constitution, an amendment goes to the state legislatures for a vote.
Another way to use the fridge for brief cold stratification is to plant the seeds in individual jiffy pellets and put them in either a plastic covered container (such as for home baking little bread loaves) or in a store-bought greenhouse flat. Depends on how much room you have in your fridge.
In horticulture, stratification is the process of treating stored or collected seed prior to sowing to simulate natural winter conditions that a seed must endure before germination. Some seed species undergo an embryonic dormancy phase, and generally will not sprout until this dormancy is broken. The time taken to stratify seeds depends on species and conditions; though in many cases two months is sufficient.