I've tired looking it up on the internet but multiple plants of similar appearance came up which has gotten me all confused. Best guess is that it's either black mondo grass or a new Zealand flax but im not sure. Any idea?enter image description hereenter image description here

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It's either a Cordyline australis or Phormium - the answer to this question will decide; when I look at the base of the plant, it looks like there's some slightly woody stems where it's been cut back previously, which would indicate Cordyline rather than Phormium. Cordyline forms a semi woody, fairly narrow trunk over time, with the growth at the top, but if you cut it down, it just sends out new shoots from the base. Phormium, on the other hand, never forms anything even remotely woody, it simply spreads sideways with similar, soft topgrowth. Only you can know if this plant has been cut down at various times... Image of Cordyline here https://www.rarepalmseeds.com/cordyline-australis-purpurea

If it's Phormium (which is the more likely ID primarily because of leaf colour) there are two types - Phormium cookianum and P. tenax. The latter get much, much bigger in the ground than the former, but each type has a wide colour range in terms of the leaves - yellow, red, purplish/black, variegated, striped and so on. There are several black cultivars such as 'All Black, 'Back to Black', Platt's Black and others - hard to say which precise cultivar this is. Phormium is commonly known as New Zealand Flax.

  • Great to hear from you again. I checked the base and it doesn't have that woody feel to it. More like dead skin that peels off so im guessing it's phormium. As per the cultivator, like you said, its hard to say. I got it off a friend who was about to throw them out cause he was told that they die in the winters and thats all the info i have on the plant. Nov 7, 2019 at 22:15
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    In the second photo, bottom right hand side, it looks like there's the stub of a woody stem that's been cut down, that's why its hard to be 100% its Phormium and not Cordyline. If that isn't firm and woody,then its Phormium - either way, it would be best to remove all that moss from the top of the soil in the pot and just check whether it needs repotting... though that's best done in spring, not sure where you are.
    – Bamboo
    Nov 8, 2019 at 1:16
  • Yes, I'll probably wait untill spring to do that. Im sure it needs repotting. I did clear the base of all the moss to check for wood but all i see is clumps of leaves so i guess its safe to say that it's phormium. Thanks for the help. Nov 13, 2019 at 14:19

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