Are they newly planted? If so, you should wait to fertilize until after they bloom. Also, 'yellow' often means the drainage is not up to snuff. I usually have around 8 drainage holes in the bottom of my pots (covered with screen). What kind of mix did you use to pot up your roses?
Judith

Coated timed release fertilizers don't release unless they are mixed with soil, not just scattered on top. Generally, any reasonably balanced fertilizer is fine for roses. They are just normal plants and use the same nutrients as other plants.

If all the leaves are an even light green, the plant needs nitrogen.

If lower leaves are limp and pale green, maybe with yellow veining, eventually dropping, it is overwatering. Soil may smell sewagy at the drainage holes.

Yes, as Judith said, yellow leaves, especially lower leaves, can indicate poor drainage. It is important that your potted roses drain freely and not sit in dishes of water, as is often done for other types of plants.

That being said, a little fertilizer wouldn't hurt. I'll put a link below to an informative article about container-grown roses:

Here is a link that might be useful: roses in containers

It's the new growth. Really pale. The lower leaves look nice and green. I used Miracle Gro potting soil, seems to drain good. I try not to water too much, lightly every few days, just depends on the temperature. They never set in water dishes (I learned that the hard way). I believe in good drainage, even to the point of drilling extra holes in the bottom of all new containers before planting. I had been using all organic stuff, manure-based fertilizers, alfalfa pellets and the like. Just seems like the organic stuff is not keeping up with what the plant needs.
Really, I like the idea of all organic, "feeding the soil, not the rose". but I can't reach a balance with the containers. All my roses in the ground get only organic stuff, and they look great.

I have a rose expert at the nursery I shop at..she has her own fertilizer and lots of potted roses. She also believes in healthy dirt..feed the soil so to speak. She does NOT believe in Miracle Grow. I would use Miracle Grow if I was having a swanky party in my back yard and needed fast growth..it's like crack for roses..LOL. Last weekend she gave a seminar and she did mention diluted liquid fish fertilizer for potted roses..made sense to me...

If the new leaves are an even light green, that's normal, unless it spreads downward, indicating N deficiency.

If the new leaves are pale between dark green veins, it's iron deficiency. Miracid has chelated iron in it.

Really, I like the idea of all organic, "feeding the soil, not the rose". but I can't reach a balance with the containers.

Fish emulsion at 1/2 strength every 2 weeks is an "organic" solution.

I get pale new growth when the weather is on the cold side here--how have your temperatures been?

The fish emulsion/seaweed kelp thing has been ongoing once or twice a month, still pale new growth. Weather has been on the cool side on and off.
I was thinking I might have a pH problem locking down the iron release, my well water is likely alkaline like my soil. Green veining with pale in between.

Well then, switch to a fertilizer with chelated iron. Sounds like a minor problem, though. Sometimes this clears up with warmer weather and drier soil.

If you can find someone to share the expense with you of purchasing Indicate 5 which will help with your PH level, I'd suggest that.

Here's the seaweed I use.

http://www.tampaagriculturalproducts.com/seaweed.html#seaweed-quart

Here is a link that might be useful: Indicate 5

I also believe in feeding the soil. I use Peter Beales Natural Rose Care from Organic PlantHeath Care. I also use fish/seaweed emlusion especially on young roses and in between feeding the PB Rose Care.

One great thing I found browsing the container forum is using a 'wick' to help draw the water to and out of the bottom of the pot. It really does work.

Evie, Indicate 5 is designed to lower the pH of pesticide spray water for those pesticides which are unstable at higher pH. Using Indicate 5 to lower the pH of fertilizer solutions strikes me as pointless and using it to lower the pH of either soil or of irrigation water seems like a very expensive way to do the job.

Thanks Mike...lol Can you tell I'm not a consulting rosearian...lol

I did get some Indicate 5 thought and will use it with my Rose Pride:)

I'm bookmarking this page to help me diagnose leaf color problems. Thanks everyone!

Carol