Can Milkweed Grow Fast Enough?

In warm summer temperatures, monarch larvae can grow this big in about two weeks!

Will there be enough milkweed to feed the hungry larvae?

Monarchs often arrive in the spring just as milkweed is emerging from the ground. When milkweed is in short supply, a monarch may lay more than one egg per plant or leaf. "Egg loading" is a sign that milkweed is in short supply. If milkweed were plentiful, monarchs would not lay so many eggs on a single plant. When people see milkweed plants loaded with eggs, they wonder: Will there be enough milkweed for the hungry caterpillars?
1. How would you document the growth of a milkweed plant?
2. How would you document the amount of milkweed a monarch larva needs during its caterpillar stage?