all non-organic fertilizers are produced using the haber process, which derives nitrates and nitrites from methane and natural gas. the ammonia, ammonium nitrate, and urea produced by the haber process is very soluble and is taken up quickly into the plant's system. they are, tho, ultimately carbon-fuel based.

organic fertilizers take MUCH longer to break down into useful compounds. in the long run, organic fertilizers are (probably) better for your garden, tho, metabolically speaking, there's really no difference in the nitrogen between organic and non-organic fertilizers. (plants need more than nitrogen, but here in FLA our soils are very nitrogen poor. speaking broadly, for a number of reasons floridians needn't add ANY phosphorous; and the amount of potassium required is pretty minor.)

it has been my experience that knockouts, more so than most roses, need lots of nitrogen fertilizer to look good. in the absence of ready nitrogen, they really don't grow much and bloom weakly. but, more nitrogen requires more water, and rapid growth tends to be more susceptible to insect and fungal issues... so, i'm taking out my knockouts, because i just don't find their bang to be worth the buck. there are plenty of OGRs and floribundas that look better and, i think, require less care.

for my roses, i use mostly organic rose fertilizer (espoma brand), lots of cottonseed meal, garden compost, and a couple handfulls of epsom salts that are supplemented with sulfur, magnesium and potassium (again, espoma brand -- good stuff).

a few times a year, esp now, when it's hot and very rainy, i supplement that feeding with 10-10-10 standard garden fertilizer, about 1 cup per plant. if i could find a fertilizer that was 10-0-10 or 10-0-5 (low phosphorus/potassium), that would be even better (environmentally), but i haven't been able to find such fertilizers sold in large bags.

I don't have many roses and I don't know much about the technical details, but I can say that my roses respond almost instantly to the Bayer product that comes in the big blue container. It may be junk food for them but they love it!

Love the junk food bit! My husband fed his roses sea food. As an avid fisherman, he buried all heads 'n' guts - and sometimes, spoiled bait - in the rose bed. The girls in his office quickly learned to keep a vase in their desk for when he brought in loads of freshly cut roses.

Alfalfa pellets are my roses' favorite food.
I got this hint from Blooming Idiots who I bought my OGR from and who are at many of the garden sales .

I have been using various fertilizer products on my roses, like Bayer, Scott's, Rosetone and I really haven't seen much difference in the roses between one product and the other. I have mostly Knock Outs with a Don Juan and a few OGR's. I haven't had any problem with my Knock Outs, they really always look good and produce flowers like crazy.
What I really wanted to know is which of these products would be organic and which would be synthetic and how can you tell by looking at the product.
Also, are the petroleum based products harmful to the environment?
Thanks for your opinions.

I'm not an expert but fertilizers leaching into the ground water is BAD...the quick release nitrogen and the phosphorus are the worst.

On the subject of potassium: In past years I've has soil anayalasis done for several rose gardens and found the potasuim levels to be low, too low. Potassium will leach out quickly with heavy rain. I use SPM...(Sul-Po-Mag...Sulfur/Potassium/Magnesium) to bump the the potassium and magnesium.
I like the espoma products and another one out of South Carolina Purely Organic is very good but hard to get.
I use a non organic too...

you're right about the potassium. the amount of muriate of potash (which should be considered organic, but inexplicably is not) or wood ashes (which are considered organic) needed to adjust the K level is very small. i use muriate of potash a few times a year -- just a tablespoon per plant, maybe two if it's a big well-established plant. i've never used wood ashes, but it's my understanding that very little wood ash is necessary, too.

oh, and: what's interesting about waterways in fla: they tend to be very rich in phosphorus and potassium (leached from the sand and karst), but extremely poor in nitrogen. when nitrogen is applied excessively or indiscriminately, and is washed into the watershed, it causes explosive growth in algae and (esp) introduced water plants like hydrilla.

that's why you should be very careful in applying high nitrogen fertilizers. but, the fact is: golf courses and resorts (and college campuses!) where thick green grass is "required", are the real problems here. mix the runoff from large parking lots with overfertilized lawns and drainage ditches that empty into waterways... and you have the real source of the problem.

you and me fertilizing rose bushes, while not totally unproblematic, is at worst an extremely small cause of a large problem.

Ive never heard of petroleum based fertilizers, but I can tell you that organics work great, and so do synthetics like Miracle Gro Ive used both just that I cant stand the smell of the organic stuff especially when its hot urghhh. . . but hey if you dont mind the smell go for organics a bit slower then miracle gro but works in the long run

Alfalfa pellets cost about $10.00 for a big bag and are an excellent source of organic nitrogen.
You can scatter them around the beds or put a large coffee can full into a 5 gallon bucket of water, stir it around til it dissolves and water with it.
A handful in the compost bin every now and then speeds up the composting process too.
Funny, at first I didn't think that ground up alfalfa "grass" would do much good, but it does.

Gosh, Ill, I'm surprised to hear your experiences with Knockout Roses! Of all the roses I have ever grown, they require less of...EVERYTHING. I hardly ever feed 'em, and they can get along without water longer than anything else in the bed. They look consistently green, even when the OGR's are stressed and dropping leaves. And they bloom non-stop, especially the red (original) and the pink. Both of those seem to be better bloomers and stronger plants than the Blushing & Rainbow varieties. I've never tried the yellow one, so can't say how it does.

Anyway, it's interesting that they do really well for me, but not for you. I think every single yard is a unique micro-climate, and what is happy in one isn't necessarily happy in another, even in the same Zone.

I have been trying to feed my roses better this year, and alternate between foliar feedings with Miracle-Gro and organic feeds with Rosetone. I have alfalfa pellets, but haven't used them! DUH. I need to go throw some around!

Marcia