A scary story and a question.

Last summer I received from a friend about 15 or so Iris bulbs that she had dug up from her garden.
So I planted them along my front yard fence. She did not know what color they were so that as added to the excitement for me.

Fast forward a few months,
The neighbors have come to know me out there in the yard, doing my gardening as I will spend hours on my days off working.
The Iris plants have done very well, though they have not bloomed yet. I am not concerned about that as I figure they just need to establish themselves.
Our mailman who comes around @ noon on delivery day usually waves at me, but this last Thursday he stopped to chat.
In our conversation he mentioned that he had Iris (not for the faint at heart) and that within two years,they had taken over his entire front yard.
So much so, that because he wanted a lawn, he bulldozed his entire front yard to rid himself of the Irises.
He also said that originally he had all sorts of colors, but eventually they all turned white.

Now I am wondering about the validity of his story,but I am also concerned about if this could happen, what precautions I should take, if any.

Thank you for your help,
Anita

anita,

your iris will multiply. they do not 'take over the yard' in the sense that they spread by underground roots like ivy and vinca or free seed like kudzu or nandina.
the main fat part (rhizome) of the iris will bloom and then it's 'done', not to ever bloom again. it will send out shoots on the sides which will become the flowering rhizomes for next season.

an iris will bloom the same color every year, they do not 'become all white or purple'. however, some varieties are particularly proliferative and will have 10 or more babies per year while some other varieties may only have 1 or two. so if one does not clean the beds by removing the old mothers and replanting the babies every so often (every three or so years is sufficient for most gardens),it is possible that the faster spreading variety can overtake the slower ones and the slower ones can rot or die. iris rhizomes, when not divided will grow on top of each other, i have seen them as thick as 3 or 4 stacked with the bottom ones hollow and dead.

here is a picture of how rhizomes look in the spring when they have made babies, you can see the one in the middle made a lot more than the one on the left side. the center, fat portion is the part that will bloom this year, the sides will become fat by september and each baby on the side will look like its mother by next spring:



This message was edited Mar 2, 2009 9:21 AM

editing to remove typos.

This message was edited Mar 2, 2009 9:22 AM

Sounds like your mailman maybe spinning yarns! LOL!

I've heard of yellow flag iris ( Iris pseudacorus ) being invasive in wet areas, but can't think of any white species that would do that. Could simply be him mistaking another plant for iris.

Not even the Spuria Orientalis is that invasive. Yes on Pseudoros many states have it banned to sell.

D

yup, the Pseudoros is invasive. banned anywhere near water, and it's a water iris, which can grow in the garden.

oddly enough, I've heard this same story from a GOOD experienced gardener. she started off with blue, and they all turned over time to grey white. All I can think of is they formed seed, the seed spread and germinated, and since many seedlings are a silver white, they might have been more prolific and smothered the parents. (bad idea, naughty kids!) the most prolific will take over, the weak will get overrun, as others have said. My Lady Friend has taken out both Celebration Song and Bride's Halo, in a 3 year span.

Solution--hybridize with Lady Friend for vigor. Blues & whites will produce from each other depending on the cultivar.

Wow!

That is amazing. I see how much I have to learn.
Do I need to trim my Irises after they do begin to bloom?
How do I recognize if it goes to seed?

Thank you so much for the help,
Anita

No trimming, just cut the bloom stalk off after it blooms so that the energy will be sent to the new babies. The only time you trim is when you divide them to keep the wind from kicking them out of the ground in an inverted "V" should look like this ^

Some irises have pods formed by bee action. the seed pods are large & quite easily removed. this happens less in the Tall bearded than it used to, due to more space between the flower parts. They don't 'go to seed' like some other perenials. Pods also form on the beardless irises & they also can be removed.