I think in most regions it is optimal to plant in fall for both ornamental allium and garlic. As with most things there is no black and white, clear cut answer. If you put them in the ground now I have a feeling the garlic would root and grow some garlic but not its full potential(fewer and smaller cloves than could of had if planted in fall). Allium are supposed to bloom much earlier than garlic are supposed to finish so I don't believe the allium will have enough time to properly root and get well-established before they are supposed to bloom in late spring/early summer this year. A potential pitfall for both is that they rot in the ground before rooting. This depends greatly on the weather conditions this spring. Viva El Nino!

It's best to plant flowering allium bulbs in fall, garlic in spring unless you have mild winters like me and you.

You have to ask the supplier of the flowering bulbs and/or read the instructions
on the package. But generally, flowering bulbs, including alliums
need to be planted in fall.