You can compost anything that grows or comes from something that grows, time is really the only variable.

OK, I know there are some things you are not supposed to compost such a black walnut because of toxins it contains. I know Iris is poisonous to animals because of the irisin, terpenoids and quinines so I didn't know if it would be bad for my compost also.

I miss the old threads where people would talk about composting horses and t-shirts and stuff.

You Might Be a Compost Wacko...

Have you ever composted a . . . . .

I should have been more detailed....

100 pounds of my finished compost probably started out as what, a ton or more of 'raw' materials? I have a number of toxic plants, mostly vines, and other 'never compost this' things in my bin at any given time. Everything breaks down in the bin and think about it this way - the toxic compounds in my hyacinth bean vines, morning glories, verbena, walnut, (and on and on and on ) were formed by the plant using nothing more than my soil, air and water, right? When I decompose them in the compost bin those toxic compounds break down into the what they started as... ashes to ashes, dust to dust so to speak.

I see lots of silly things said about composting on the internet and then copied, pasted and repeated to a point where it becomes the de-facto 'rule'. LOL, this is worse than science by consensus, this is propagation of ignorance.

Example - we are told that you must never compost meats or carnivore poop (dogs, cats) because it could lead to a profusion of deadly toxins, right? Well, theoretically yes, that is true. Poop that lies on my lawn won't go anaerobic and create a toxic soup but it attracts flies which can spread the nasty pathogens in it. That same poop, buried a foot deep in my hot compost pile is heated to about 170 degrees in a few hours. All the pathogens are dead in an hour at that temp including the most stubborn things like the eggs of ascarid worms so composting is much safer than 'letting nature take it's course'. Meats? Good nitrogen source but can attract vermin which might bite you or have fleas that carry diseases etcetera but in the center of my hot bin or on top of the rat-proof bin where I have about 8" of soldier fly larvae who will devour and decompose meat before it can even get malodorous I am not worried about it.

Many people mean well, they read that you should not compost X so they repeat it and there is always some logic behind it - putting a big pile of dog poop in a low oxygen environment that is too wet would be a bad idea and absolutely would present a health hazard so they say "Poop can't be composted" to avoid having some well-meaning newbie who hasn't done their research and doesn't have experience with hot composting hurting themselves or giving composting a bad name due to a few one off horror stories.

...but I prefer to get the facts and let me decide based on facts. If the advice was "Don't mess around with poop unless and until you get the knack of hot composting and consistently reach and maintain 150 degree temps in the center and see a chart showing the temp/time graph for the destruction of fecal pathogens then I can make an intelligent decision. If I just throw 200 pounds of dog poop into a pile after reading that and get sick then composting poop did not make me sick, stupidity did.

Time to get off my soapbox and turn the compost so I can dump the bucket of 'puppy presents' that has accumulated over the past day or two ;-) after 48 hours it will be baked sterile and will crumble into dust and it will be completely devoid of pathogens - this time of year my pile has lots of grass clippings and is well over 160 degrees just one foot down.

You could compost fresh vegetables...
but it would be a waste of resources.

I think you'd do better to trade the irises for coffee grounds or bagged leaves or potting soil or other kinds of plants or garden art.

That would give you compost materials (or plants or art), & it would give someone else flowering plants for the garden.

That sounds great sylvia, but the OP said that s/he could not GIVE them away. We don't know how hard they tried but this was not the question at hand. I've had the same problem, although not often. Using Freecycle, Craigslist Free section, putting it out at the office with a Free sign, or setting it at the curb with a Free sign, I can get rid of almost anything.

Back to the original question: I agree with the other posters who say composting will break down most all organic compounds in the plant material. I personally have never heard the one about irises being toxic. Your worst problem here is having them sprout. Turn the compost if they do.

oops, sorry, musta sneezed or blinked or something.

I am an iris nut, & it makes me flinch to think of chopping up rhizomes & composting them.

A couple of months ago, I dug up about a million irises from an old home;
the house had been sold, & the re-hab contractors mowed the irises down.

(pause for sylvia to recover)

so I asked, & they said I could have them.

I estimate that I dug out about 150 of those irises.

I planted as many as I had room for, gave away as many as I could...
& I still had about 25.

I put them on ebay with a "buy it now" option...
& sold them within the first 10 minutes.

They now live in Maine.

This post was edited by sylviatexas on Fri, Jul 4, 14 at 23:18

You can microwave them so they won't grow. Chopping them up may not work. Cook in the oven and then maybe liquefy in the blender. Sounds like too much work to me, just put them in the city wide green bin if you have one of these.

This post was edited by tropical_thought on Sat, Jul 5, 14 at 8:43

Sorry Sylvia, it pained me also, but I did try. I have 3 flower beds that got totally overgrown with weeds and flowers due to an injury last year that made it impossible to care for. No one else in the house had interest. This year I recruited help to weed and thin. The Irises totally had taken over two of the gardens. If it makes you feel better they are indeed sprouting up in the compost pile and I have been relocating them along the edge of the woods! :)

When we thin our iris, we put them out in a box with a big FREE sign and they are gone in a day! Nancy

This must refer to smaller wild type Iris and not those big one with the big flowers? I can just easily take one out of the ground. I can't see them taking over the whole garden. The bulb comes out cleanly in one shovel dig.