Can I successfully sow sorghum &/or buckwheat before last frost?

Thanks, cuz just got a field plowed & our winter is dragging thru spring here, with warm days, but frozen nights. Not every night and not deep freezes. I'm in zone 5, Canadian Rockies. Thanks, also cuz i feel a cover crop is important to "armor the soil", attract bees, transition to no-dig Regenerative Agriculture. We partic need to regen soil here, cuz this was forested, so soil needs building here anyways. And yes, I'm planting trees too.  Thanks, Nick

I grow both at high elevation in Northern Utah in a 85-100 frost free growing season. (Last week of May to first week of September)

Thanks. I was afraid during the tender part of buckwheat or sorghum's development that either would succumb to frost, or actual dips into freezing temps. That's what we're still getting here, warm days & frozen nights, but only when sky is at least somewhat clear. So I sowed rye & oats, peripheral alfalfa and some kale seed from last year. Thanks for reminder. I still have to turn off sprinkler. To a springy spring. & don't forget to reforest so to avoid a silent spring, book title from 1963 by Rachel Carson. BTW, I loved the Uintas back when i was there over 20 years ago. An east-west running mountain range is something to behold, partic given how mtn ranges usually run north-south, so yielding layers of geology while driving along that east-west running hwy. Bests, Nick

I plant them in warmer weather, say after the apple trees have flowered.

Hi, Did you mean rye & oats or kale &/or alfalfa?  Nick

I had volunteer kale, daikon radish and buckwheat seedlings coming up. A cold front came through and killed most of the buckwheat. Kale and radish seedlings survived. Not sure about sorghum, but rye over winters here.

Thank you, also cuz now i don't have to cloche off kale seedlings, as my partner said i should. But building a cloche or two is a good thing either way, given the vagueries of the weather. Our clear nights still are frozen. I guess that's not off kilter for zone 5.