Draye's right, unless your blue rooster is split for lavender (which is possible as there are more people using blues in their lavender programs, although it is still generally not recommended because both blue and lavender are genes that dilute black pigment and you could get some unpredictable results using two different color modifiers at once) you will need to keep the lavender rooster in order to get any lavender chicks at all.
The lavender rooster with the lavender pullet will produce 100% lavender chicks. The lavender rooster with the black split pullets will produce 25% lavender chicks, 50% black chicks, and 25% black chicks split for lavender (I think, I'm not positive on the hatching statistics for lavender splits and it's a little early in the morning for my brain to figure it out reliably yet).
The blue rooster with the black split pullets (assuming the blue is not also split for lavender) should produce 50% black chicks and 50% blue chicks. Although I'm not sure if blue and lavender can both be expressed on the same bird or what that would look like, so there's an unknown that I can't describe. I'm not sure what would happen with the lavender pullet and the blue rooster, I don't know enough about lavender genetics to really guess. And it's early.
I've started a Lavender project and need some advice on which roo to keep the Lav or the Blue. I have 3 pullets 1 lav and 2 split black. I feel like an idiot for asking but I have a hard time understanding the genetics when they are explained in terminology I don't understand. I'm not a newbee on chickens just on breeding. Thanks
