Obviously the best thing is to have your soil tested and get a fertilizer especially mixed for your needs. Otherwise 5-10-10 is a good substitute.

Hmmm... not obvious to the novice, actually. Wouldn't have thought of it. Thanks for the pointer!

Jessie

Well, the two types of fertilizer they send are supposed to be specially blended for irises, and the one they have you use for fall planting is a 0-13-18 formula. I don't imagine I can find this anywhere in stores and I am nervous about how long the shipment will take since I just ordered it, so should I try what gmason suggested and get my soil tested at the garden center for a custom blend?

The Cooley's fertilizers are inexpensive (though shipping is not). I'm getting antsy about planting these bulbs they delivered to me a couple weeks ago... they are aired out and just waiting to pop in the ground!

Bone Meal is the best choice for fertilizer. When searching for iris fertilizer, make sure the first number (nitrogen) is no higher than five.

Carlos

Carlos thank you so much. A hardware store employee handed my mom a bag of Holland Bulb Booster, which is 9-9-6, and that struck me as a little higher than I was aiming to go. The product claims to be "better than bone meal" but I've never heard of the brand so I'm not sure about it.

Should I just use bonemeal? I have seen others mention both bonemeal and superphosphate (I think) applications.

Either way you've been a big help already. Thank you Carlos!

Jessie

Carlos,

After visiting your page, I hereby defer to any and every bit of knowledge you have to impart regarding irises! What a beautiful site, and gorgeous iris pictures!

Jessie

Thanks for visiting my webpage, although I am few and far between the authority on Iris. I will say that bone meal is all I ever used for fertilizer. Although I heard of super-phosphate, I've never actually seen it here in Chicago.

Carlos

I'm shocked at the Holland Bulb Booster fertilizer ratio.

I learned from a specialist (doctorate) in agriculture about the difference to plant roots between superphosphate and bonemeal.

Superphosphate is immediately available to plant roots so you must dig it into the lower soil so it won't come in contact with new roots immediately. I use about 6 inches soil between the distributed (dug in) superphosphate and the rhizome and haven't had a problem.

Bonemeal is not available for several months (maybe he told me a year?). New roots are fine touching it.

That's why I try to use both when preparing a brand new bed.

HI iris_gal,

Thank you so much for your response. Yeah, I am just learning about these things, but it didn't sound right to me either. What you say is very interesting, and probably more in-depth [both literally and figuratively!] than most explanations I am likely to encounter on this information quest of mine. I am going to head to a couple of the better garden centers near me today and I'll also be returning the bulb fertilizer.

I just can't bring myself to put my first irises in the ground until I'm satisfied I'm preparing it the right way, as much as possible before I have to stand back and wait impatiently for next spring to show me the results.

Thanks again for everyone who's responded thus far!

Jessie

I add bone meal and limestone before planting (soil in Georgia lacks lime), never add fertilizer until the plants are established. Works well for me.

Hi there, I don't mean to upset the apple cart here, but the initial recipe you have for your soil is, in my opinion, a recipe for disaster. I looked up Bumper Crop on the Master Nursery website, and it's high nitrogen. You're defeating your purpose of searching for the correct preplanting fertilizer if you're going to amend the soil with such a high nitrogen amendment before planting. According to the Master Nursery website, the east coast version of Bumper Crop has liberal amounts of blood meal, cow manure and chicken manure... all nitrogen additives. I also have heavy clay and have come up with my own soil recipe (if you're interested, the recipe is on my web page under planting instructions). There's also a suggeted blend for planting on the American Iris Society website. Since you're much more northerly than me, the recipe on the AIS site might prove a better choice in your environment, or perhaps someone else here would share their recipe with you. Either way, I strongly believe amending with Bumper Crop wouldn't be the way to go. Ev

marvine, thank you for your response... I used to work at a garden center and never actually learned about using lime to amend. Thanks for your input :)

blissful:

Wow, what an eye-opener. I am extremely glad I read your post before I put the remaining 19 irises in the ground! Bumpr Crop is almost a prerequisite for most gardeners in our area so I was surprised to read your advice... surprised but grateful! I would love to read your recipe. And lastly, thank you for directing me to the Iris Society site. I'll be poking around your site and the society's pages next.

Jessie

I hadn't used bone meal until last year after having dogs dig up a newly planted bed years ago searching for the bone.

I decided to try it last year in a new bed. I got about 99% bloom in that new bed with plants I ordered last spring. This has never happened before, and I attribute it to the bone meal. What I got was bone meal powder and not the granulated form I used years ago. This may make a difference in the way the plant absorbs the fertilizer.

I have never seen such weird ratios as 0-13-18 available in garden centers or co-ops. I have been having trouble finding 5-10-10. The lowest in large bags has been 10-10-10. Here lately during the summer, I have been shaking rose fertilizer (9-18-9) from the canister. It has been doing well in keeping fans green and not bleached out in the heat. There has been summer growth as well and not dormancy. My last application was in July and won't be adding this in the fall for fear of fast growth at freeze-up.

I hadn't used bone meal until last year after having dogs dig up a newly planted bed years ago searching for the bone.
I too found I can't use bone meal with having dogs. They will dig anything and everything up, looking for the bone.
I found this out the 'hard' way.

Sue

Hmmm...wmores and chemocurl, I have a big dog who loves to grab anything she deems edible, so that's definitely a consideration for me.

Speaking of holes, I feel like I have gone down the proverbial rabbit hole with my iris fertilizer question... I just don't trust the 9-9-6 stuff because, well, no one has suggested it to me. It claims to be "better than bonemeal" on the package so I assume it contains none. I guess I am going to break down and have my soil tested... and soon!

Jessie

I have a big dog who loves to grab anything she deems edible, so that's definitely a consideration for me.
I think you are wise. Years ago, I carefully planted some tulips, mixing a little bone meal in each hole, and my doggies did not rest until they had dug every last one of them in the hopes of finding 'the bone'.

Sue

In the spring when I am spraying for leaf spot before it shows up, I put in Miracle Grow 'Bloom Booster' at 1/3 strength along with Dial Liquid Hand Soap with Tricoslan, or a generic that does as well.

Hi wmoores,

I actually bought Miracle Grow Bloom Booster... glad to hear I can actually use it on my irises. But would you recommend only to use it at the diluted strength and in the springtime as a spray? That's neat about the Dial as well; we use that for our handsoap.

Yes, dilute Bloom Booster to 1/3 to 1/2 the recommended dosage, 1/3 until you know how it works in your climate and conditions. With the soap, I just put about two tablespoons in the gallon sprayer. It will stick to the foliage and make it really glossy until the rain washes it off. It is said that this is a rot preventive. Out of 550 named varieties and nearly 1,000 sdlgs., I had only one iris to show signs of rot this summer, and I live in an area that averages 60" of rainfall normally, but we haven't had a normal year in ages. In 2004, we got over eighty inches of rainfall, some of that was from remnants of two hurricanes. I haven't been able to check my rain gauge since the rainfall started from Gustav. It has rained constantly for three days and was the hardest this a.m. with the final remnants passing through. I have forgotten what the sun looks like.

I don't have a dog now but skunks, my cats and the neighbors dog will dig things up if I use bone meal so I mix in garlic powder. This seems to help so far. I put it in the front flower bed with garlic powder and a repel-it to keep the wild turkeys away and it seems to be working. My husband had this neighbor lady who used only bone meal on her iris and he said you walk into her back yard during blooming season and it was breathtaking. I wish she was still around when I met my husband. I would have liked to seen that. When I use it on acid loving plants, I dig a hole put it in cover it up then put sulfur on top of it.

Chere

wmoores, thank you so much for that recipe... I plan to use it.

Chere, that's a great idea.. .I am also thinking of using those bulb wire grid boxes to be extra safe since I know for a fact that we have chipmunks and moles in our yard.

Jessie

I have never heard of burying garlic with the bone meal to keep dogs or critters from digging it up. That's very clever. I have never had a problem with things digging up small amounts of bone meal buried in iris beds. I think the big point here is iris are different than growing many other things. They will do better if you never give them any nitrogen or manure. But they do like bone meal.