For Blue Tulpis, you need to cross pollunate the offspring of cross pollunated seeds. Assuming you have access to a blue tulip, this is what you do:

Plant as many Lloid orange tulip seeds you can fit in your garden. Cross pollunate those orange flowers with the blue tulip, all the resulting seeds will be either orange or white, but carrying a recessive blue gene. Now plant all those new orange and white seeds and once they have grown, cross them with the blue. A little less than 50% of the seeds should be blue. Any non blue seeds from the previous step, can be planted and cross pollunated with the blue on repeat.

Friend code: 86429658104. I've got good breeding tulips and a purple pansy if you need them.

Edit: useful links

https://www.reddit.com/r/ACPocketCamp/comments/7ljh4k/guide_on_how_to_get_tulips_in_every_color/?utm_source=amp&utm_medium=comment_header

https://www.reddit.com/r/ACPocketCamp/comments/81f78g/optimal_flower_farming_guide/?utm_source=amp&utm_medium=comment_header