Canna Selection Advice

Whats the general rule for planting out "tubers" of established Cannas which ahve been overwintered?

Will I need to wait for 1st June to be sure we are past any cold weather? or are they not fussy about having at 10C minimum (like Tomatoes and Cucumbers etc.)

I've only got seed-raised plants, so beginning of June is fine this year, but I might struggle in future years to bring-on the 100 or more Cannas I have if I have to keep them protected until 1st June !

 

You can plant out any time after the last frost, its just better if you can grow on a bit longer under cover or potted to get early flowers.

Back in the mild winters I used to leave them in the ground until Feb, then dig a few up to divide and bring on in the greenhouse to flower earlier.

I found they were overwintering in the ground OK back then, but would not flower until mid august if just left to grow in-situ.

 

Pete - how do you coax them back to life after the winter. Do you let them produce shoots first and them water, or water a bit when they have no shoots. I grew a few from seed last year, and kept them frost free over the winter, but they haven't produced any shoots. I suspect that I have overwatered them, though I tried hard not too. The rhizomes still appear to be firm, but I suspect that they are gonners.

Your Cleopatra is going great guns and I would hate to lose it, and I don't want to lose my C. tuerckheimii, which is already huge.

The problem must be similar to Dahlias - but I don't seem to have any trouble with them.

 

Difficult to say Peter, they should actually start to move even without water as the temperature rises, if they are alive.

With the winters we have been having recently I'm coming round to the idea that you you need to bring them under cover early, whilst in full leaf.
Its only that way that you can dry them off properly.

A soaking wet root ball cut back and brought into the greenhouse during Nov is likely to rot.

I'm thinking yours should be shooting now Peter, if alive, but dont give up on them just yet.

 

Thanks Pete for the info. Thats a good idea of letting them dry out slowly - still with their foliage.

 

Sorry Armandii, if it was my suggestion, at least you know they are alive.

 

I've got some C.altensteinii ready to go out, they are in pots in the bottom of "blow away" greenhouse, they are put out every day to harden off and have also stayed out a couple of nights when the temp was mild. They are about 12-18" now so will be planted out in another week or so.

I grew these in a very large pot a few years ago and when it finished flowereing and I'd got some seed from it (late august/early september) I reduced watering and let it dry out and by early October-ish it was dry and the foilage was yellowing off. I moved it under cover then before the temp dropped too much or it got too wet from the autumn/winter weather.

The following spring it started in to growth without watering; I began to water a little when there were several 1-2" shoots.

With the really cold winter last year even my 'dry' pot of these; wrapped in fleece, straw etc bit the dust. Have to make an extra effort this time to get them through......

 

Bilbo - thanks for that info. I am tempted to not water, in the spring, until the rhizome has put out some shoots. After all, it can't really use any water until there is some growth to exhale moisture.

 

I'm not sure if it was on here or another forum but I saw a photo of Canna growing in a pond somewhere. I would like to try some in my small pond.

Any ideas anyone?

 

Canna glauca and its hybrids are the ones to try, they are the true water cannas, in theory though most cannas could be tried in a pond when they're in full growth as they consume so much water

 

I've grown them in my pond, just in pots though.
They are slow starting, probably because the water needs to warm up.
So I put an established plant into the pond late June.

I've only tried a couple, both yellow flowered, one was from the seed Sal brought back from Thailand.
The first one I tried was a yellow spotted variety, but I cant remember the name.

Certainly saves having to water them.

 

LongK I`ve got they thai cannas and the stuttgards both in water , but and say but !!!!! they don`t grow as fast as the one in the soil so you`ll may end up with a tiny canna by the end of the season and as Pete say I`ve not dared to leave them in water too cold ....