Hi triple b.

I have been going insane on this subject this summer. Don't know if you have chlorotic problems beside the bud, but I have had same along with brown edges. So far I've removed 10 dahlias and now I suspect Verticillium wilt, a soil fungus which interrupts the plants' ability to uptake water.

Although I believe this is a question for plantlady or poochella, I might add that my remaining plants looked somewhat better after an application of liquid low nitrogen fertilizer and lots of water.

the foliage looks fine. But things (tomatoes) have looked a touch chlorotic in the past so I will get some seaweed fert or something. Thanks

well here is a DUH moment. Seems the ones that looked yellow on the outside of the buds were in fact....YELLOW DAHLIAS.
I thought that one was Penngift, a lavender. Turns out it is Honka. The other yellow-budded one is Inland Dynasty. (I wonder where I planted Pennsgift?)