cold hardy flowering trees?

[crust]

Many people in your zone have great luck with a subterranean open trench dug into the ground, snow is allowed to cover and accumulate over the trees. a mesh top is fitted to deter vermin. The depth of several feet really helps keep temps regulated---however, if you have even moderately tight soil this can become a nightmare pond/ice-rink and depending on topography, often hard to load and access. I suspect your best bet is to capitalize on the waste heat from your home and heal your trees in with mulch against your foundation, preferably on the north side. You may need to make a lean-to snow deflector if snow dumping is a concern. Possibly removable. covering your trees with snow is imperative and a key to winter health, even if you must shovel your yard to do it. One thing though, while not all trees are relished by vermin, fruiting trees are. My experience is, eventually, insidious chewing vermin will descend on your trees, they always wait until they are at their very most refined state then they go crazy and chew everything to smithereens. The only known way to avoid this, if they are out of doors, is to encage them in 1/4 inch hardware cloth somehow--mothballs, peppers sprays etc, are ignored the year they decide to visit. This is why I house mine in a special wintering quarters building.

 

[Leo in N E Illinois]

I have Amelanchier, still in Anderson flats. Super winter hardy, zone 4 and into zone 3 if you choose the local native Amelanchier. Smooth gray bark like a beech, white flowers before leaves, edible fruit early summer.

 

[Leo in N E Illinois]

Don't forget witch hazel, autumn blooming, after leaf drop. Native into zone 3, collect local ecotype from your woods to get the locally hardy genotype.

American hazelnut & American filbert (beaked hazelnut) are equally hardy. Flowers not as nice as witch hazel but nut husks make good winter interest.

 

[Leo in N E Illinois]

The northern lights deciduous azalea have a few listed as hardy to -40F, their growth habit tends towards long internodes, but I imagine if one were to keep after them you could do medium size bonsai with them.

 

[crust]

The northern lights deciduous azalea have a few listed as hardy to -40F, their growth habit tends towards long internodes, but I imagine if one were to keep after them you could do medium size bonsai with them.

I have a friend who had a nice one of Very tough Nice flowies and overall really nice tree. He allowed it to be filmed in the winter and the Newmans lights toasted the tree and sadly it croaked.

 

[makarovnik]

I recently got a wintersweet. yellow fragrant flowers. Mine did not flower yet but I have something to look forward to.