Iris with brown holes

I have gotten a iris bev sills and it has brown holes and it looks also like tiny holes what can it be.I thought rust,so i added to water with bleach,It looks like a couple others near it has it too.anyone know??

It's probably leaf spot which is a fungal infection. There are many thoughts on what to do for it. I alternate daconil and Bayer systemic because fungi can become resistant.
http://www.oznet.ksu.edu/dp_hfrr/extensn/problems/IrisLeafSpot.htm

Bummer, huh? Some people only take off the infected leaves since it's not supposed to kill the plant, but I've found that it certainly can take a toll on them.

Don't walk through the leaves when they are wet. It spreads the infection.

Sorry that you have to deal with it. I'm finding that Messenger applied after the infection is cleared up stops from recurring.

If you're talking about tiny holes on the underside of the rhizome, that's where old roots have died. It's perfectly normal and nothing to worry about.

Laurie

I am going to try and get a picture If i can get my camera to work it has been acting funny lately.Then i will post Robin

i found out the iris has a disese I read about and it spreads to others in your garden so know i gotta but expenisve sprays.wanted to let you all know when i get camera working i will take pic's Robin

tiny holes and the leaves are turning brown could mean iris borers. ugh. my most hated thing.

LOL, Laurie... I found a few iris rhizomes with just those sort of holes, didn't realize those spots were just where old roots had died... broke away and threw out the worst looking ones... which was fine, as they were probably old "mothers" as you explained to me in another thread.

I did find a small, pale yellow maggot looking critter.... What do iris borers look like? And does that bleach soak (20 minutes in 9 parts water, 1 part bleach) kill them with certainty?

I put on my new "headlamp" tonight and weeded the iris bed... much better than working in the heat of the day! With the soaking rain we had again a couple of days ago, the weeds are really thriving... the good news is that, once I cleared everything else away, my irises look like they're thriving too! Now I need to get my new ones planted out.... :-)

Borer larvae have pinkish bodies with dark heads. The larger they are, the pinker they are. Bleach soak does NOT necessarily kill them.

Laurie

Nope it doesnt i found alot more I have to go out and pull all those that where affected alot of work robin

Well, I broke apart a lot of clumps when preparing these new iris for planting, and I found only one tiny thing (3/16" at most) that *might* have been a borer (yellow-cream, not pink, and tiny black spot at head end)... hopefully it was the only one! (I squashed it, yes I did.)

a picture of last year's iris borer horror in my garden.
this time last year, almost to the day.

Oh no!! That's what I saw in one of my new iris clumps.... only Janie's monster borer is about 20 times larger than the one I squished! Hopefully the bleach soak took care of any others... the iris certainly looked very healthy, and I didn't see signs of damage to any of the rhizomes.

What are the signs of borer infestation? What should I be on the lookout for??

brown spots on the leaves (like pinpricks)
if you catch these when they are young you can squish the little things IN THE LEAF before they get to the rhizome.

If they get to the rhizome, the leaves will one by one turn brown. The holes will look brown all around the pinpoints.

When you dig one up you'll find a worm where the rhizome is supposed to be. Strangely, the iris may have even bloomed. But they eat the rhizome and cause bacterial rot that must be cut away.

You also have to remove the rotten soil around the place where the rhizome sat in the ground.

Dig up the rhizomes, soak them in bleach, cut out the rotten parts and KILL the worms so they won't make the flying monsters that lay the eggs.

THen make sure you don't have debris around the irises when spring comes ... that's where the little guys show up, where the eggs were laid. YUCK!

Hope you can eradicate them. I've not had much luck, they come back over and over again. :(

Well, I will hope against hope that little one was an isolated incident.... and I will be on the lookout!

Thanks!

I have to redo my beds now that is what I had.It went from one to another what a mess

I am new to this forum, but not at all new to iris,have been growing them for over twenty years. The borer has been a big problem in the past but so many people in this area are using Bayer Grub Control with Merit. It should be spread very early in the spring as borers hatch when the temp reaches about 70 degrees in the spring. so spread it lightly around the plants early . The people who have used it say it has totally done away with the borer. I think you will probably have to continue to use it each year. Not much can be done once the borer has been in the rhyzome but to clean it up and replant the healthy parts. The moths will hatch in August but you are not likely to see them as they fly at night. The eggs they lay will hatch next spring so that is when you want to apply the Grub Control. Be sure it says with Merit

*making a note about using Merit*

Thanks!

well I just dig out all my beds it took me 3 hours Now to get the work all done before we hit winter

Hi guys,

I'm brand new and my name is Kristy. I came on here to find out how to deal with these borers. I got 'em too. And irises are almost the only flowers I grow. ;( My garage bed was almost entirely filled with Bearded iris. And now they're all dead. I dug up a few and the rhizomes were already eaten and there were those grubby looking borers in there - ICK!!!! I think I might have rescued the SDB iris that was on the far corner of the bed, but I planted it in a pot to make sure those *&%$#* things wouldn't spread. I think I got lucky and they left the back bed alone.

I think Sutton's sent me the borers! ACK! Because I've had irises for about 3 years now and never had any problem with them before. But, I also divided them for the first time ever, last fall, and wasn't 100% sure of what I was doing. I dug them up, divided them, then replanted the little rhizomes all in the same day. Now I read I was supposed to let the cuts on the rhizomes "heal" before I replanted them? How do I do that? Wait a few days? So, could I have divided the rhizomes wrong and the scent of the newly cut plants attracted the borers? I'll have to find out if the people I gave my extras to got borers also. I ended up having 500 or more little rhizomes, ACK! What a job!

Anyway. So, my other theory is that Sutton's sent them to me. Because I had already established irises (the replanted, little rhizomes) in both beds. And I ordered new iris from Schreiner's and Sutton's, last year. Now, the back bed only had old iris and some from Schreiner's and it's fine. But the garage bed also had Sutton's and it's swarming with those nasty things! I recieved too incredibly small iris from Sutton's (besides other, big ones) and they were the first to turn to mush.

So, long story short... I threw out all the iris (except 2) from the garage bed. One is in a pot and the other is on the back hill, where there aren't any other iris. So, what do I have to do to get rid of these things? Will I have to dig up as much soil as I can and get rid of it? Then put some borer poison or something down, too? Now and then again in the spring? If I don't plant iris in the bed for a year, will they go away? HELP ME, PLEASE!!!!! AHHHHH!!!!

Kristy... weeping, because they got my last Conjuration iris. ;() WAAAAAHHHHHH!!!

Kristy,

I'm very sorry to hear about your borer woes, and I'm on my way out to the barn so don't have time to address your other questions right now. I do want to assure you, though, that you did NOT receive borers from Sutton's. Borers don't exist on the West Coast, so you will not find borers in any irises from that part of the country. IL, however, is borer territory. If you have not had them in your garden before, it is probable they migrated into your garden from a neighbor's garden or from a wild iris population nearby.

If you search this forum for threads on iris borers, you will find LOTS of important and useful information on their management in iris plantings.

Laurie

Thanks, Laurie.

Oh yeah, Sutton's is on the West Coast, duh! I didn't want to think they sent them to me, because I like that company. So, I feel better ~ in a way ~ now. I have been reading up in the iris forum and have found a lot of useful posts. Especially from you, LOL! So, I think I have a pretty good idea of the battle I have ahead of me, now. Only problem... we have a compost "heap" in the back. When we have leafy garbage, we just throw it back there. And this thing is HUGE! I've thrown the remains of my bored out irises back there. Besides leaf litter, etc. It would be almost impossible to go through it and find the iris remains to burn it or whatever. So, am I just screwed now, because the eggs are in there? I'm thinking of just trashing all my irises and starting over in 2 years. (Give the soil a year to clear out.) Cause I only have 8 to 14 left. I had about 40 or so. ;( I dunno.

Thanks, I'll post when I have more questions, lol!

No need to start over. You will probably have borer eggs hatching again next year, but if you apply Merit very early as irises are just breaking dormancy in the spring, the Merit will take care of the hatchlings. It's all in the timing.

You pretty much have to assume that if the borers didn't come in on irises you acquired elsewhere, they're in your immediate neighborhood and will probably always find a way into your garden (remember that borer moths can easily fly from one garden to another to lay their eggs). That's why Merit is so indispensible. Use it every spring, and you'll be able to keep your borer problems to a minimum.

Laurie

Yes, that Merit stuff sounds great. Can you apply it too early? I'd think earlier would be better, no? Also, I was wondering, do the iris borers harm any other type of plants? I guess the moths lay their eggs on anything? I read in one of the threads that they don't lay them on green leaves, but they will on nails and bricks, etc. So, yeah, I guess getting rid of my few remaining iris isn't the solution.

A woman a few houses from us has irises in her front yard. So, they might've come from her. I don't know if anyone else around here has any or not. Seems like on our side of the street, there's mostly men that don't garden, lol. But, I do know irises (the flags - found regular blue, plus yellow and red!) grow wild in the forest preserve about 6 blocks from our house. So, I guess it was just a matter of time before I had borers, huh? It's just odd because I've grown them for 3 years and never had any problems before. Hmmm. I dunno!

Thanks for all your help. It's a daunting battle I have ahead, but, like you said, if you can get them when they're small, it shouldn't be nearly as bad. (I've been thinking about staking out the garden in the middle of night and killing any moths I see, LOL! Of course, I'm afraid of moths, so that would probably just result in screaming and running, LOL!)

This message was edited Aug 13, 2006 1:39 PM

Iris lover 79--I am from your part of Illinois and I know how the borer can drive you crazy. Merit does work, don't give up on iris. I used it for the first time last year and this year I have not spotted a single borer. Oh Happy Day ! I have been growing iris for about 20 years and when I first started I did not have any problem with borers for several years, like you I thought I caught them from some plants I ordered. But the truth is it takes them awhile to find a nice juicy bed of iris, but when they do, they move in. I do not see any adverse effects to using it. I belong to the Northshore Iris and Daylily Society, we meet at the Chicago Botanic Garden. If you want to contact us for assistance, the Botanic Garden will give you a phone no.

Hi uallady,

Thanks for the info. I know where Des Plaines is, you're pretty close to me. Merit does sound really great. I hope it works as well for me as it has for everyone else. I do think it might have been my fault that I got the borers, for two reasons. First, last fall was the first time I ever divided them and I didn't let them heal over before I replanted them. So, the smell of a "nice juicy bed of iris," to use your words, probably wafted throughout the entire bug kingdom, lol. And also, I graduated from college this May and really neglected my garden this year, because I had so much homework to do and such. So, my beds got overgrown with weeds and I left dead iris blades in the bed (thinking it would be good compost, doh!)... so that probably created a great habitat for the borers. Sigh. Well, I'm only going to take a few computer classes this fall, so I should have enough time to prepare for battle. It's daunting to think about, but iris are my favorite flower, so I will fight. I never thought of giving up on them entirely. Just for a year, if it would've helped the borer situation. I might check out the society you mentioned. Iris are my favorite flower and lilies are my mom's (I think she likes the Oriental ones the best, but she has a ton of daylilies, too.) Thanks again!

~Kristy

We don't have the dreaded iris borer out here in Wyoming but my sister- in-law in MA has them bad, she lost many iris. Another thing to use is Dimethoate (Cygon) & Lindane both are effective control against iris borer, but check the label if you can use in your area

Cool, thanks Mainecoon!

~Kristy (have I hijacked this thread? Ooops, sorry!)

iris lover 79 - I am still planting even though it is getting late. I have found that a very worthwhile investment (in time) is to cover new plantings with straw once the ground has frozen (usually about Thanksgiving Time in our area) The year I used straw covering I did not lose a single plant but another year that I didn't bother I lost almost 3/4 of the new ones. It is kind of a mess to spread all that straw and a bigger mess to clean it up in the spring but in our crazy climate it is worth the time and effort. I'm also going to use it on my new daylilys too. Without the straw the plants heave out of the ground with the freeze and thaw cycles that we have a lot of. I am putting a light application of Merit between the plants this fall in case some of those criters are still in the soil. Hope you can come to our iris show at the Botanic Garden the first weekend in June. There is also the Northern Illinois iris society that meets in Hinsdale. They have their shows at the Morton Arboretum ( that spelling doesn't look right) You can really learn a lot from other members and have some fun too, everybody can enter in the shows and maybe win "Best in Show" or the silver medal for the most blue ribbons.

I still have sitting in my cool basement the irises I bought in a co-op here on DG.
I am afraid to plant them but I think they may be dying so I have to do something.
Would they do ok in my raised beds till spring when I can relocate them to the garden?