@gardenglassgems
Apologies for the late response. This is an excellent time to plant Alliums. I've never used mulch with mine. Frost protection not necessary for most alliums. Good drainage is essential (a little sand mixed in the soil may help).
Aflatunense should work well.
Christopfiii have only lasted at best a couple of years for me.
Karataviense only bloomed well for one season for me, couple returned, then they too, were gone.
Siculum should work well. (aka Nectaroscordum). Bulbs smell like garlic but the hanging bell flowers are very neat in the garden As the flowers get pollanated, they start to stand up like shuttlecocks. Make a neat cut flower if arranged over the viewer.
My favorites are White Mt Everest (very tall white with softball size spheres and A. Schburtii - almost other worldly w/ and outer sphere a foot in circumference and within the pedicals of varius lengths shoot our within the outer circle. Really a wondrous show off allium. However, these have shown a propensity to work well once, if the season is warm in winter they may return. These are originally imported from stock grown Israel and don't seem as hardy as most of the others. Their out of this world presentation is worth their presence.
Most alliums add a neat architectural dimension to gardens filling space as the garden finish the spring blooming blooms and start summer mine stays like lilies, daylilies, and perennials.
Full sun is usually a necessity . I wouldn't worry about watering them in summer as they doubtlessly appreciate the dry side after blooming, I've never fertilized mine either.
Looks like RJ gave good guidelines.
Wishing you an allium successful spring.
