Cover new irises with straw for first winter?

I'm a TBI newbie in zone 4/5. Schreiner's recommends "covering newly planted Iris, especially in areas with cold winters. Soil, straw, pine needles, and leaves are all effective covers. Remove the cover as early as possible in the spring." I have a lot of old hay, but found in the past that it got moldy by Spring when piled on plants (roses) for winter protection. Does anyone out there use straw to cover new irises for the winter? If so, how much do you use - a couple of inches? more? Thanks for any advice you have for me.

we never cover the iris with anything in willamette valley oregon

We use pine needles when the ground is frozen to protect against heaving. the ground here does alternate freezing & thawing so heaving is possible on MDBs or newly planted irises--like now. If ground is frozen & stays that way not necessary except for the first year.

Pine needles - great idea! I have boatloads of pine needles, and they don't mold. Thanks, irisMA.

Pine needles don't blow in the wind as bad as leaves do either. Right now our Ponderosa pines are doing a good job of mulching our iris gardens without much help on our part. lol

Edited because my fingers & brain don't work at the same time

This message was edited Oct 12, 2010 10:34 PM

I like cooperative trees.

Last year our forum 'talked' about Alfafa suppliments and DH went out & bought me 50 lbs of Alfafa 'cubes'. What a dear! I made the 'tea' & used the 'straw for covering the Iris. I know, I've read that it really doesn't help that much...but I had the most awesome blooms this Spring, ever! :o)

I had 20 lbs. left so went ahead and made the tea for one last watering and will use the 'mulch' to cover those more exposed.

Who knows what may make a difference? It's kind of why we take a vitamin each day.

We have pine trees that also provide for a nice weed barrier and so forth for plants. However if I don't remove most of it in early spring it will choke other things out too.

Husker I had to laugh about he alfalfa pellets from last year. We rushed right out and bought a 50lb bag and it's still in the shed. LOL I don't recall reading about making a tea with them. I thought I read where you actually worked them into the ground. Either way I still have a 50 lb bag I need to use. Maybe I'll toss about half of them in a 50 gallon drum and let it set for a couple of days and then dip it and use it on the plants. Then again maybe I should save them until the end of February and then make the tea. I just know some years I have a much better bloom period than others. I think alot of it has to do with the weather and mother nature and not so much as what we do.

Ok, another test I'll forget the results of. I'll make a tea drench for the irises right now and use it on some of them. Then I'll make another one in the spring and use it on another flower bed. Then I'll leave one iris bed alone and do nothing to it and compare all three.I just wonder what the differences will be in the long run.

Going to the shed and digging out alfalfa pellets to make tea.
Hope you are all having a delightful weekend. The weather here has been very nice, cool and crisp. We have a chance of rain this Tuesday.

Marian

You are a lady after my own heart for I 'love' to experiment. It kind of makes gardening more 'fun'. A 'few', probably 8 years ago, I purchased on QVC~ 'Bill's Perfect' fertilizer 6-11-5. Every couple weeks I sprayed it on all the plants in my rock garden,(this was b-4 my Iris 'olic' Mania set in) and it truly was an awesome product. All my neighbors (3) asked about what I was using? Or maybe they wondered why this old lady was hand spraying flowers all the time. The main ingredients are Phosphate 11% and Total Nitrogen 6%. Why would that simple spray produce bigger & more plentiful flowers?

I haven't used it on my Iris because I'd read the first number should be the lowest. Hmmm, '6' isn't that high. I feel another experiment coming on for next year.

Oh my goodness that flowerbed is beautiful. Is that purple plant a begonia, astible, or what? I love the blue spruces are whatever they are in the background too. You have a very lovely place dear. I've been looking for something to use on the pastures to keep the weeds in check. It looks like grazon is going to be the best best.

As for your hand held spray fertlizer I don't see a problem with it for right before the irises start to bloom. I've been known to use 10-10-10 or 13-13-13 on my irises on more than one occassion. I can honestly say I've had the best results by adding the bagged black cow manure and work it in very lightly.

I didn't get the alfalfa pellets out of the shed today. Instead I got the Liquid Eraser out and painted it on all the broad leaf weeds in the front yard. It was a chore but if it works it will be very worth while. I'll watch closely and see if I get good results. I'm going to use the preen in early spring. I'm not going to continue pulling weeds the rest of my life. I just can't keep up with all of these wonderful gardens and so forth I've surrounded myself with.

Happy Gardening, everyone.
Marian

Looks like a purple Corabell. I just happened to buy 4 for my wife this spring.

Welllll........I love to use pine needles as mulch. Corn gluten or preen or any preemergent for weeds.......problem I have is I like to sow seed of salvia or larkspur, johnney jump-ups, evening primrose, or poppies in the fall to bloom in the spring with the iris for a cottage garden effect...can't cover the seed or use the weed preventer..Sooooooooooo I just have to hand pull weeds and by hot summer they get the better of me. I work like a dog in the cool months of fall trying to pull out the perinnials. Hope that is spelled right I can't ever seem to remember

I am sure Lovely can attest to the horrible properties of that dreaded Burmuda as well as crab grass in our area

Burmuda grass is aweful ... it has taken over one of my daylily beds. I've really just about given up. I was thinking today that I might just dig them all up and put them in pots for the summer. Then spray that bed a half dozen times with round-up and try to get rid of the burmuda grass. That would be a lot of work, but I've been trying for years to get rid of it and I can't seem to win.

av_ocd_girl,
Hi Yield grass herbicide (purchased from COOP) can be sprayed over the top of irises and daylilies to kill the Bermuda grass and it will not bother either flower. Bermuda grass may require spraying a couple of times to kill effectively, and adding a surfacant such as Dawn dishwashing liquid will effectively "wet" the grass and ensure coverage with the herbicide.

Marian,
I also will occasionally use a 4" paint roller to "paint" the weeds with Roundup when it is windy or there is danger of getting the roundup on the irises. I will mix the roundup in a 5 gallon bucket and use a long handle attached to the paint roller to keep from crawling and bending to a minimum--just dip and roll--works quite well. For broader coverage, use a 9" roller.

Wow! Thanks for the tip on Hi Yield... I had no idea there was something I could spray on it that wouldn't kill anything else. I'm going to go look for it today. Wonder if I could use it this late in the season? I'm sure the bottle will tell me.

Thanks

Roxanne

hi- yield? will it kill the wildflowers or just the grasses?

I live in NW IL and all my iris are in raised beds. Not real high, about 4", just enough to stay out of our hard pan wetness in the spring. I DO cover all my iris with straw every year, usually around Thanksgiving. I wait until the ground is frozen, but get the straw on before it might thaw and refreeze as that's what hurts them. I use 3/4 of a bale of good long straw per 4'x16' bed. Make sure you shake it out nice and fluffy. You will be surprised how it really hangs onto it's self and doesn't blow away like you'd think. ONE year I did not cover them, and we lost 80%!!
I take the straw off in early spring. Depending on the weather. If it warms up early like this year I took it off in march, usually it's early april. I try to get the straw off and rake out as much seed as possible or I have all those sprouts to pull.
I should say that the iris I have scattered around my other gardens, that are not raised I do not cover and they seem to do fine. Those however are not watched closely, and are generally overgrown clumps that I don't dig orders from, so they may loose some rhizomes and I don't notice.

Thanks for sharing your method, sunshineannie. My iris bed sounds very similar to yours - 4'x20' and 4" tall. I have a bunch of old hay that i could use, and i also have gobs of pine needles from our "shedding" ponderosas. Maybe i'll try half the bed in hay and half the bed in pine needles, and see which half fares the best.

I don't know if I'd use hay, I think it might get too wet since it has dried leaves in it. I'm lucky that my cousin farms nearby and drops off what I need. I do buy it from her of course.

I forgot to say that I have left my iris untrimmed, and also have trimmed them before putting on the straw. They are much happier in the spring if they are trimmed before covering. Plus it's much easier to get the straw off w/o all those tangled iris leaves in the mix.

The last statement is why we cut back the siberian foliage in the fall. The people inour area often use salt marsh hay (no seeds) for a winter mulch. Obviously doesn't work in Illinois/

After reading about all the weeds that pop up due to hay cover, i'm now leaning towards using all pine needles. I'll have to collect them soon - we had our first light dusting of snow of the season last night.

I would be worried that pine needles would pack too much and hold the moisture. The reason straw works is because it stays fluffed up and holds the temp. constant. It doesn't pack down around the iris, and acutally forms sort of a dome when it's frozen.
The idea is to keep the soil from freeze/thaw/freeze/thaw..... The iris themselves can take the cold, but not the heaving caused by the soil freezing and thawing over and over that breaks the roots off.

Our pine needles don't seem to pack. They are put on after ground is frozen if the snow cover doesn't get there first. I dread ice.

I've been using pine needles for several years, and have had no difficulty with the soil retaining too much moisture. I have just completed preparing my iris beds for the winter. See attached picture. In the spring I just make sure that the pine needles are cleared from on top of the rhizome & increases. I leave the needles on throughout the year to keep weeds down.

That looks great! But your pathways are too narrow for my power chair! I think by the time my DH digs and replants Bed #3 next year, all we will have on our one acre are iris beds and pathways! At least I will be able to get close enough to use my hula hoe on the weeds.

Wow, Dennis! How many and how long are the rows? Are they your seedlings? Don't you dare not come show pics in bloom!

How many irises do you have, HappyJackMom? I think a yard with just iris beds and pathways would be wonderful.

I put a layer of pine needles on my TB Iris this year after learning from Polly to use them on the Siberian and Japanese Iris. I also used them on the Daylilies along with some leaf mulch.
I did not use to heavy a layer as they had established pretty well with the long fall and we did not freeze until this week. The Sib and JI Iris did very well that I am testing for Polly and the pine needles helped a lot there.

Hi Polly. We have probably only 150 different cultivars, but several hundred rhizomes divided and replanted this year. But we ran out of time, it was 30° this AM, so we will have to wait until next year to do the rest. We spent a couple of hours this morning putting pine straw on the main beds, in 45° weather. But at least the sun was shinning. I had to come in early because I could no longer feel my hands. How come hide on cattle keeps them warm, but leather gloves don't do the same for my hands?? LOL

Cattle heated from within ha ha

Polly,
My raised beds are 32 feet long. I have 5 beds that are ~5 feet wide, and 4 beds that are ~2 feet wide. The 5' wide beds each hold around 90-120 plants (clumps), and 2' wide beds ~50-60 plants(clumps). In addition, I have 6 other beds each holding from 40 to ~120 plants(clumps). I now have just over 600 varieties, about half of which I have 2 or more plants(clumps). My seedlings are in other beds -3 that contain ~1200 plants, and one that has been re-selected down to 5 varieties and a total of ~30 plants. I also HAD three other beds that are still under rubble of trees/branches from an ice storm in Jan. 2009. A couple of these beds will have to be uncovered and reconditioned next year, as I have about 1200 seeds from this years' crosses that will have to be lined out next summer.

HappyJackMom, My goodness, that is amazing! Were you still dividing until just recently? I'm still dividing. It works here as our soil doesn't freeze, so I can divide right up to the first snow.

And Dennis, OMG, I can't imagine. Have you introduced any irises yet, or are you new to hybridizing? What a set up!

Wow what an undertaking Dennis. Have you pics. of the seedlings if any have bloomed. This sounds so wonderful. How long have you been doing this??
Steph

O M G !!! Can't even imagine taking care of that many plants. Yes, please show us pix.

Polly,
No, I haven't introduced any irises. I just enjoy seeing what results from specific crosses. I completed my first cross in 1995, but did not keep any records of parentage. I started again in 2006, and have been keeping records of what I have hybridized. I will have to slow down hybridizing in the future, as I am getting to the point of having too many seedlings to take care of and places to plant them. This year I'm sending ~240 seeds from 12 crosses to lovelyiris for her to plant as I only have tubes for ~1200 seeds.
Following this post, I will post a few of the more interesting seedlings that have flowered and increased reasonably well from my 2006 & 2007 crosses.

Here is pic of my 1995 cross--parentage unknown

A105A-17-- Amain X World of Color

A105A-20 -- Amain X World of Color

A105B-01 Amain X Lets Be Friends

B28-02 Laced Cotton X All Aboard

B280-11 -- Frosted Fantasy X Apparent Secret

B280-21 -- Frosted Fantasy X Apparent Secret