Tip with grow flowers from seed

I'm going to try my hand at growing some flowers from seed. The three I'm going to get started on are Cleome, Asclepias and Columbine. They all have instructions regaurding pre-chilling them, all between 2-3 weeks. My question is how important is this? The instruction are to sow the seed and put in the refrigerator for five days. Has anyone done this before and have any tips? Is five days enough or even needed? Any input is appreciated, thanks.

 

I have never tried growing these particular plants from seeds but have grown various other types that require chilling so I would recommend following the instructions - I once experiment with some kiwi seeds and those that I did not pre-chill for 60 days did not sprout. FYI, columbines are found growing wild (or use to) in quantity in the lower mainland so you have to imagine the seeds dropping in the fall and then overwintering in the ground.
Without pre-chilling the seeds often will not germinate, or will not germinate properly.......some plants need that cold, dormant period into order to set properly.

 

I find that the same thing works for poppy seeds. Either plant the seeds in the fall or chill them before you plant them in the spring.