Most likely a result of damage from last winter - very often, they produce new shoots from the base or up the stem, if yours haven't done this, then its just wait and see what happens, there's nothing much you can do to keep them going other than watering when in drought

Chances are your cordilines are suffering the effects of an insect called thrips there tiny little offspring feed from the plants sappy leaves or swords These microscopic pests do an enormous damage to foliage, especially plants with reed like leaves, and are often present for a good few years, even cold winters dont always shift them, the remedy is a chemical called "sprayday" made by bayer, pay around £7 from your local(independent) garden centre don`t settle for any other product, this insect needs its ability to feed inhibiting a process called clogging, other insecticides work differently, within a few weeks your cordilines will recover, Gladiola bulbs bought from the B & Blues of this world often introduce these mites to your garden, always use your independents when buying plants, a proper nurseryman would spot the problem before the plants are sold to the general public

If its thrips, you should see a fine, silvery white mottled discoloration on the upper leaf surface. I'm still going with winter damage...

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Oh dear, Davidlee, don't get your pants in a twist - I'm fully entitled to my opinion, but if you wish to have a different one, I have no problem with that, fill your boots up. The purpose of answering questions is to inform the questioner - I have merely added some info to your suggestion of thrips, and then reiterated my own guess, for that's all it can be without photographs. Have a nice day.

David - welcome to GOY, as we haven't met before. I hope you enjoy the site as much as I do.

Please let me say that everyone is entitiled to their own opinion, but that I have the utmost respect for Bamboo - her horticultural knowledge is deep and full of experience. I've learned a lot from her (and others) on this site.

Please don't be so discourteous to her or anyone else, or you'll be upsetting more members, too!

There has been an awful amount of damage done to cordylines this year due to the cold winter, as this question section can prove. I would suggest that you take on board both answers and examine the plants thoroughly for signs of Thrip (and possibly add a photo of the effected areas) If you can not find any then go with the alternative.
If you do a search for "damage to Cordylines" in the search box, (top right of the page) there will be lots of questions and hundreds of answers available which might add some light to the situation.

Good luck with them and I hope, whatever is causing the problem, you can get it sorted as soon as possible.

I am in no way an expert gardener of any kind but hope I can in some small way offer an option.

Ian.

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Is there something in the air at the moment, or what ;-)))))

Zzzzzziiiiip !

I reckon there is, Louise, one can sense trouble brewing, its bubbling up here and there, must be something in the stars, lol! I'm not rising to the bait though, so hope that puts your mind at rest (Louise, that is). David can think whatever he likes about me, it's no skin off my nose, it's only his opinion, though I'm not happy about his insult to other members - interesting, though, that Davidlee has no information about himself on his profile page... seems to go along with not being able to take a rational, balanced view. I seem to recall another person last year who was similar... As I understand it, this thread has already been flagged.