For anyone who likes to garden and likes to get plants started early for transplanting into ground or big flower pots or whatever, cardboard egg cartons are fantastic. You put your soil into the cups, pop in your seeds and set the cardboard on plastic or an old cookie sheet and water. When the seeds sprout and it’s time to plant them, just cut the cups apart and plant the whole thing in the ground. The soft cardboard of egg cartons is very biodegradable and makes it easy to plant your flowers or veggies.