Hi, Pardalinum ..
Cannas are NOT lilies. Totally different family/species. 'Lily' is used from yrs ago & I wish it'd be 'dropped', as it's misleading .. it's only a 'common description' in reference to flower shape really.
I'm in Australia & grow, collect & breed many cannas & various iris, incl. different Bearded Iris & others.
The area where I live has very hot summers & very cold winters .. s'times with snow & always with frosts. Temps range up to 40'c in Summer & down to -10'c s'times at night in Winter. We often suffer droughts for months.
Although there is no need to dig up & store cannas here (unlike many areas of the USA & England & Europe), I do mulch heavily over the rhizomes in the coldest part of the winter.
I also reduce watering in winter as the cold can freeze the moisture in rhizomes, which will then split & rot. They are trimmed to just above ground level when they are all died down.
They reshoot as the weather warms in Spring, but late frosts will s'times burn new growth, so do not remove the mulch .. it'll help retain moisture in the hotter months as it rots down to add nutrition to the rhizomes for new growth & flowers.
It's best to 'feed' Canna in mid Spring with natural composted organic animal manures & well composted plant materials, but NEVER use old canna cuttings .. it may promote diseases specific to canna & rust.
If you have a large wide garden, plant your canna where it's well drained, but with moisture retaining soil. If you are planting with B.I's, I'd suggest you plant the B.I's in front/edges/borders but raise their soil level like a swale & plant the canna at the back as a 'backdrop' but lower than the Iris bed, so water drains back to the cannas. You'll see both the foliage of the canna & the flowers because they'll grow taller than B.I's .. even 'dwarf canna are likely to reach 3ft tall in many varieties, including 'Orange Punch'.
Canna are best divided after at least 2yrs establishing & never allow canna to totally dry out or rhizomes will become weak, thin, twist & flowr & grow poorly. I'm happy to help with any canna q's .. varieties & canna names s'times vary from country to country, but I'll help if I can. :)
