I`m planning to grow a 15 sq. ft. section of canna rhizomes this spring. They will be planted in ground with additional fresh soil, full afternoon sun on the south west side of the house zone 7b. Should I mulch them right away upon planting? (will be using a layer of shredded cedar mulch) Any further info. is appreciated. Thanks

Really need information about the existing soil.

I find cannas dead easy in the clay...

at my house in the sand hills... can't hardly grow them.
canna.... ginger... turmeric (curcuna sp.)... all like plenty of moisture.

so... yes, if you have mulch available to you... definitely use it.

Dead easy!
They won't care about mulch. Though, leaving them not mulched may help them get warm. Give Plenty of water. .Without mulch I guess you'll get some crabgrass.
Are they the tall Canna indica with relatively smaller red flowers, or hybrids with bigger flowers?
Indica are monsters for me, give them room between rhizomes.

We have a fine patch of canna, been in the ground about 5 years. It is easy to grow on our river bottom silty loam in full sun. The only thing I know of that can set them back is freezing temps. Hence the mulch. We cover ours in late fall with coarse compost 4 to 6 inches thick which, even with a hard freeze, protects them. Zone 8b. Once things start to warm up, I pull up or scatter most of the mulch.

You are just out of Canna happy range so I think your main obstacle will be to keep them from freezing to death in winter. Your southwest exposure next to the house is a good start. After that, a thick layer of winter mulch. Bury the whole bed in several inches (the more the better) of straw or leaves in winter and hope for lots of warming sunshine.

with Lucy.
But next fall, I would dig some out and store inside, to be safe.

Lucy68 said: You are just out of Canna happy range

I love cannas!

Two big boxes of canna rhizomes were dug last fall and stored in my unheated but frostfree basement in my zone7b.
They'll survive the winter right against my house foundation, and sporadically further away without mulch.

Our cannas here grow in straight sand. That's what we have in Florida, and that is what they grow in. Never had any problems with that. I don't personally mulch the garden. But it can't hurt at all. It could also give you the extra layer of winter protection

Gina1960 said: Our cannas here grow in straight sand.

Florida is different from the (Carolina) sandhills...

1) it rains a lot more in Florida
2)Much of florida is on top of those limestone caverns with water almost reaching the surface...

And, I would ask whether you irrigate... And how far down the sand goes.

Also... What part of Florida your gardening experience is...

I do have small patches of canna that haven't died... But, when I was in the clay, They thrived enough to dig tubers for the stew pot....
They were actually aggressive growers there...

I'm in No Central FL at an elevation of 177 ft. The Aquifer here is over 200 feet below the surface, not 'almost reaching the surface'. Our well is 225 ft deep.
It only rains generally in the monsoon season, June-August. March, April, May can be very dry. Sept, Oct and Nov are usually pretty dry too, and its still summer temps. Some winters are wet, some dry. This winter has been wet.

Rain in Florida is usually generated in the form of thunderstorms. In winter, the 'convergence' is caused by cold air from the West and Northwest coming in and running into really warm air here in the state. So most of our 'cold fronts' are preceded by a little rain.

In summer the convergence is cause when the East coast seabreeze meets the West coast seabreeze. The two air masses hit over the center of the state and generate thunderstorms, many of which can be severe.

No, I don't water my yard unless its been unusually dry and we are in the 90's. Then I only water selected things. Like coleus. The gingers, palms, cannas, craniums, and everything else just have to make it on their own. And they are usually just fine.

The sand goes all the way down to the aquifer. There are some places that have clay layers deeper down. My place has clay in a single area, and that creates a natural bog. The areas under cultivation do not have a clay layer.

I have had the big Red Russian canna in a flowerbed for 22 years, it is so aggressive I have to dig some out of it will take over the whole bed and I have other things planted there that I like.

Hmmm...
When I went camping in Ocala, I saw how dry it was there... Was surprised that there weren't any blackberry briars on site...

Dunno what the difference is between your property and mine... I can only report my experience.... And at my house... They do not prosper.

Also... I plant wax myrtle, and plant it... It dies...
Grew great guns in the clay... How about at your house?

Wax myrtle grows wild here. You can't get rid of it, and we have wild blackberries everywhere. They are dangerous. If you fall into a big patch you will get cut up.
Our rains are 'seasonal'. They are sort of like a monsoon season. How much we get in a season depends of whether we are in an El Niño climate pattern, or a La Niña.
It also depends on if we get any tropical storms or hurricanes. We have been significantly impacted here by the three I's...Irma, Ian and Idalia. We got a lot of rain with each one of those storms

The OP is in New Jersey, zone 7b, outside the usual hardiness zone for cannas. That's what this discussion is about - winter protection for growing cannas outside their zone.

Gina1960 said:

I love the leaves on that canna, do you know what the name is?

The top one is Kaleidoscope, the 2nd is Rissian Red

Lucy68 said: The OP is in New Jersey, zone 7b, outside the usual hardiness zone for cannas. That's what this discussion is about - winter protection for growing cannas outside their zone.

So sharing extra bits of knowledge and experience is discouraged on the pages now? Many people have success in zone 7A with cannas with a heavy mulch.

Not at all, just an attempt to bring us back closer to the OP's problem.

Cannas are sold as warm weather annuals in the nurseries here, nonetheless my neighbors a few doors down planted some cannas along their side fence in the fall. I questioned their hardiness and suggested heavy mulch, they seemed to think all would be okay. Haven't talked to them in awhile... I guess there's no way to tell until spring if they've survived, but I'll be happy to report back if they return.

Several tropical plants can make it in 7A with a heavy mulch. Hedychiums, Cannas, some (not all) Alocasia and Xanthosoma, and some Musa

Canna will easily survive up here without mulch as long as it's the regular red kind. Now the others can be iffy and depends on your microclimate and where exactly they are planted. If you want to mulch around them, it won't hurt them any and in the long run will break down and enrich the soil.